US20060228794A1 - Incubation and/or stroage container system and method - Google Patents

Abstract

A container assembly (10) comprises a vessel (21) for containing a biological medium, gametes and/or one or more embryo(s). The vessel (21) has a CO₂permeable seal (28) and a closure device (30) for selective access. A buffer chamber (60) for a CO₂enriched atmosphere at least partially surrounds the vessel and is defined by a shell (61). The buffer chamber is in communication with the CO₂permeable wall. Such a container assembly is particularly adapted for IVC in which case the permeable seal (28) prevents ingress of vaginal secretions. The buffer chamber (60) mediates the aqueous pH in the vessel after the container assembly is removed from a CO₂enriched environment.

Description

BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates to an incubation and/or storage container assembly for gametes and/or at least one embryo and in particular for such a container assembly adapted for use in intravaginal incubation and culture for humans or other mammals.
• 2. Description of Prior Art
• Conventional in-vitro fertilization (IVF) techniques are notoriously complex. They involve aerobic and sterile culture of embryos in Petri dishes at 37° C. in a 5% CO₂enriched atmosphere which requires cumbersome and expensive equipment such as a CO₂incubator operating 24 hours a day during the two or three days required for the fertilization and culture. It also involves delicate manipulations requiring the skills and dexterity of a laboratory biologist.
• Intravaginal culture (IVC) has been developed and comprises maturation of gametes, fertilization of oocytes and embryo development in a sealed container filled with a suitable culture medium which is then placed in the vaginal cavity which serves as an incubator. This technology is disclosed in Ranoux U.S. Pat. Nos. 4,902,286 and 5,135,865. It is designed and utilized by assisted procreation specialists in their offices or clinics.
• To date, IVC procedures have been performed with a polypropylene Cryotube manufactured by Nunc of Kamptrup, Denmark, which is closed after loading the gametes and sealed in a polypropylene Cryoflex envelope also manufactured by Nunc. IVC procedures using such a container assembly have numerous drawbacks. Many of these drawbacks are overcome with the container assembly disclosed in Ranoux et al U.S. Pat. No. 6,050,935. That patent describes a IVC container assembly comprising a container body and resealable closure means for selectively opening and closing a container body orifice. The container body has a main chamber with a cylindrical sidewall and a microchamber in communication with each other which permits the movement of one or more embryo(s) into and out of the microchamber. The microchamber has sidewalls of optical quality permitting microscopic inspection of embryos. The microchamber also facilitates the retrieval of one or more embryo(s) by means of catheter without endangering the embryo(s). The container body is equipped with various valve designs which are either bulky or complex construction and/or uneasy to operate. A two-piece capsule of soft flexible material envelopes the container for lodgment in the posterior fornix.
• When such a IVC container is taken out of the posterior fornix of the vagina, the outer capsule is removed and the embryos in the microchamber may be inspected under a microscope. One or more embryos is then retrieved from the microchamber by a catheter for transfer to the uterus. This is done while the patient is being prepared for the transfer of the embryo(s). The entire procedure is also designed to be carried out in an obstetrician or other assisted procreation specialist's office with a minimum of equipment.
• One of the advantages of the IVC procedure is that fertilization and culture are carried out intravaginally where the atmosphere is naturally CO₂enriched and the amount of oxygen is much lower than of the ambient environment. Both properties are acknowledged as being beneficial, see Alan O. Trounson et al., Handbook of In-vitro Fertilization, CRC Press, Inc., 1993, p. 97 and Misao Fukuda et al., “Unexpected Low Oxygen Tension of Intravaginal Culture”, Human Reproduction, vol. 11, no. 6, pp. 1996, 1293-9. Likewise, the temperature is that of the natural environment of the vagina. Once the IVC container is removed from the vagina, it no longer benefits from this ideal natural environment. It is also known that the intravaginally CO₂enriched environment ensures the pH in the container is relatively constant and about 7.3 and that a lower level of CO₂in the container will cause a drop in the pH of the biological medium in which the embryo(s) reside. A relatively small change in the pH (say 0.5) may have drastic consequences over a long period of culture on the embryo(s).
• An object of the present invention is to mitigate such drawbacks of known IVC containers and to provide an improved incubation and/or storage container assembly system and container system components and an improved method for incubation and/or storage of gametes and/or one or more embryos.
• According to one aspect of the invention, a buffer chamber for CO₂enriched atmosphere is provided and cooperable with the vessel containing the biological medium gametes and/or one or more embryo(s) and is in communication with a CO₂permeable wall of the vessel. With such an arrangement, the vessel will remain in a CO₂enriched environment even after it is removed from the CO₂enriched incubation environment in particular a vagina. Thereafter, the CO₂enriched air in the buffer chamber will be able to enter the vessel and compensate for any fall in the CO₂level inside the vessel and thereby mediate the pH in the biological medium. Indeed, it has been found if such a buffer chamber is provided on the incubation or storage vessel, the pH level of the biological medium in the vessel will fall only slightly over the period of about one or two hours after the removal of the container assembly from the CO₂enriched environment. Such a small dip in the pH level does not have any significant effect on the embryo(s) in the biological medium.
• According to another aspect of the invention, a buffer chamber is provided, comprising a shell mounted on the vessel with a CO₂permeable seal disposed between the vessel and the shell to prevent the ingress of liquids or other viscous fluids, in particular vaginal secretions while allowing the inflow of the CO₂enriched air from the surroundings and in the case of intravaginal incubation, from the vagina. In practice, the CO₂inflow rate of the permeable seal will be greater than the inflow rate of CO₂through the permeable wall of the vessel and very much greater than the CO₂outflow rate through the shell wall.
• According to another aspect of the invention, the shell is mounted for movement on the vessel between open and closed positions. The shell will be in its open position when the container assembly is introduced into a CO₂enriched air environment, such as a vagina in the case of intravaginal use, and is closed as soon as the container assembly is removed from the CO₂enriched air environment. In such an embodiment, the CO₂enriched air outflow may be virtually nil during the period between the removal of the container assembly from the CO₂enriched environment and the retrieval of the embryos from the vessel for transfer to a recipient, thereby ensuring CO₂equilibration in the biological medium.
• In the course of residence in the CO₂enriched intravaginal environment, the level of oxygen in the buffer chamber will reach the favorably depleted O₂level which prevails in the vagina. Thus, after the container assembly is removed, not only is the air inside the buffer chamber advantageously enriched in CO₂but also reduced in O₂.
• According to an embodiment of the invention, the vessel is provided with a closure device including overlying disc-shaped valve members, each with an orifice, mounted for relative angular movement between an open position for access to the interior of the vessel and a closed position for sealing off access to close the vessel.
• According to an embodiment, the peripheral flange of the outer disc-shaped valve member has a peripheral sidewall radially beyond the peripheral flange of the inner disc-shaped valve member. One of the peripheral flanges has protrusions selectively cooperable with cutouts in the peripheral sidewall in the other peripheral flange when the valve is in its closed position. Preferably, the peripheral sidewall of the outer disc-shaped valve member has one or more hooking members for snap fitting axial retention of the outer disc-shaped valve member on the inner disc-shaped valve member and/or a peripheral flange of the vessel.
• According to a preferred embodiment, sealing material is affixed to one of the disc-shaped valve members for fluidtight or rubbing contact with the other of the disc-shaped valve members. Where required, an additional sealing cap for impeding the ingress of vaginal fluids overlies the closure device and is in sealing engagement with the closure device and an upper portion of the outside wall of the shell.
• One or both of a pair of opposed sidewalls of the microchamber has an abutment for docking a catheter at the desired location. A portion of the associated recess may define a lens face for viewing one or more embryo(s) in the catheter during or after retrieval from the microchamber.
• The inner wall surface of the main chamber of the vessel tapers towards the microchamber. Thus, when the container assembly is received in the posterior fornix, that is in a substantially horizontal position, except when the recipient lies on her side, the inner wall surface slopes to a small zone, where gametes will tend to congregate, thereby enhancing the probability of contact between sperm and oocytes.
• According to another aspect of the invention, there is provided a shell for surrounding the vessel and defining therebetween a buffer chamber for a CO₂enriched atmosphere. According to a preferred embodiment, there are at least two shell parts and a gas flow passage between respective ones of the shell parts. Preferably, there is a CO₂permeable seal located in the gas flow passage for allowing the inflow of CO₂enriched air and impeding the ingress of fluid, in particular vaginal fluids into the buffer chamber. Such a shell may enclose various kinds of IVC vessels and in particular IVC vessels with closure devices for selective access to the interior of the vessel. The shell is preferably made of a smooth, rigid transparent medical grade material and sized and configured for accommodation in the posterior fornix. With such a shell no separate container sleeve or carrier is necessary.
• These and another objects and advantages of the invention will be brought out in the description of embodiments given by way of example with reference to the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
• FIG. 1 is a longitudinal sectional view of a first embodiment of the container assembly with its closure device in an open position.
• FIG. 1A is an enlarged longitudinal sectional view of the lower end of the vessel of the container assembly to illustrate the catheter docking abutment in the vessel wall.
• FIG. 2 is a view similar to that ofFIG. 1 with the closure device in a closed position.
• FIG. 3 is a perspective view, from above, of the fixed inner disc-shaped valve member of the closure device for the vessel ofFIG. 1.
• FIG. 4 is a top plan view of the fixed lower disc ofFIG. 3.
• FIG. 5 is a perspective view from above of the rotatable upper disc-shaped valve member of the closure device taken on its own.
• FIG. 6 is a perspective view from below of the rotatable upper disc-shaped valve member ofFIG. 5.
• FIG. 7 is a perspective view from above of the upper part of the container assembly with the closure device in its closed position.
• FIG. 8 is a longitudinal sectional view of the container assembly including the container sleeve or carrier for lodging the container assembly in the posterior fornix.
• FIG. 8A is an enlarged detail of the vessel wall and lower valve member to illustrate the congregating of oocytes when the container assembly is lodged in the posterior fornix.
• FIG. 9 is a longitudinal sectional view of a second embodiment of the container assembly in the open position of the buffer chamber, the closure device being in its closed position.
• FIG. 10 is a longitudinal sectional view similar toFIG. 9 in the closed position of the buffer chamber.
• FIG. 11 is a perspective view, partially cut away, of the container assembly ofFIG. 1 received in an isothermal holding block for maintaining the temperature of the vessel and its contents and inspecting the embryo(s).
• FIG. 12 is a longitudinal sectional view of the upper part of the container assembly according to a third embodiment which is a variant of the embodiment ofFIGS. 1-8.
• FIG. 13 is a perspective view from above of the sealing cap, illustrated on its own, and part of the third embodiment ofFIG. 12.
• FIG. 14 is a longitudinal sectional view of the modified rotatable upper disc-shaped valve member, taken on its own, according to the third embodiment ofFIG. 12.
• FIG. 15 is an enlarged cross sectional detail illustrating the angular abutment between the upper rotating disc-shaped valve member and the lower fixed disc-shaped valve member of the third embodiment ofFIG. 12.
• FIG. 16 is an exploded perspective view of the entire container assembly according to a fourth embodiment of the invention.
• FIG. 17 is a longitudinal cross sectional view of the entire container assembly of the fourth embodiment in its assembled and closed position.
• FIG. 18 is a longitudinal sectional view of an upper part of the shell of the fourth embodiment.
• FIG. 19 is an enlarged scale cross sectional detail illustrating the label holder on the inside wall of the lower part of the shell of the fourth embodiment.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
• The first embodiment of thecontainer assembly10 for incubating and/or storing gametes and/or one or more embryos is illustrated inFIGS. 1-8. Such a container assembly is suitable for intravaginal incubation or culture (IVC) of human or mammalian embryos, and for use as a storage and transport container for gametes and/or one or more human or other mammalian embryos.
• The terms such as “upper” and “lower” are used by convention in the specification and claims, in respect to all embodiments, to refer to relative positions in the container assembly as oriented for example inFIGS. 1 and 2. It goes without saying that such terms are not intended to be in any way limiting as to orientation or location of the container assembly which in actual practice will vary depending on the stage of the procedure in which it is employed.
• Thecontainer assembly10 comprises aninner vessel20, also referred to as the vessel, the vessel having aclosure device30 for opening and closing access to the interior thereof. Theinner vessel20 is at least partly surrounded and preferably substantially entirely surrounded by abuffer chamber60 comprising in the illustrated embodiment ashell61 cooperating with theinner vessel20.
• Theinner vessel20 comprises an upper,main chamber21 and a lower,microchamber22 in communication with each other. Theinner wall surface23 of the main chamber tapers towards the generallyparallelepipedic microchamber22. As the upper end of the main chamber in this environment is circular and the lower end is substantially rectangular, the contour of the inner wall surface varies from a circle to a rectangle. The overall shape of theinner wall surface23 is generally frustoconical with transverse sections that are somewhat flattened oval shapes. The portions of theinner wall surface23 which lead into wider sidewalls24 of themicrochamber22 are generally flatter than the portions of inner sidewall which lead into thenarrower end walls25 of the microchamber. At least one of the opposed walls, here sidewalls24, are of sufficient optical quality to permit inspection under microscope or other magnification instrumentation. In practice, themicrochamber22 and in fact the entire vessel will be made of a medical grade material of good optical quality, such as polycarbonate. A polycarbonate which may be suitable is Makrolon RX.2530 45 1118 available from Bayer Chemicals. This polycarbonate has a CO₂permeability of the order of about 43.0 cm³×cm/m²×24 hr×atm. at standard temperature and pressure. Preferably, however, the vessel body is made of a crystal polystyrene, such as Nova High Heat Crystal Polystyrene, ref. 1204. Regardless of the constituent material, the vessel has aperipheral flange26 extending radially outwardly from the upper end thereof.
• Theclosure device30 is provided at the open upper end of the vessel body and comprises in a preferred embodiment avalve31 including two overlying disc-shapedvalve members32,42. One of the valve members is fixed and the other is mounted for relative angular movement. In practice, thelower valve member32 is fixed by ultrasonic welding to the upper end of the vessel in practice, the peripheral flange thereof. Each of the valve members comprises acentral panel34,44 having a port ororifice38,48, adapted to be brought into registration in the fully open position of the closure device and out of communication in the fully closed position of the closure device. Each of theseorifices38,48, is of the same D-shaped contour in the illustrated embodiment. Such a D-shaped contour may limit the access area to permit the entry of only the thinnest of catheters or the largest of pipettes. Obviously, other contours are possible, in particular circular, such as disclosed in the third embodiment. The contour edge of one of theorifices38,48 and preferably theorifice38 in thelower valve member32 has a raised lip orbead39 for enhanced sealing engagement with the underside of thecentral panel44 of the upper valve member. The upper surface of thecentral panel44 of the lower valve member has another, second, raised lip orbead40 spaced from the first raised lip orbead39 and of C-shape as shown, which extends proximate to the outer periphery of the solid portion ofcentral panel34. The second raised lip orbead40 ensures that thecentral panels34,44 of the valve members remain parallel to each other to avoid leaking.
• Each of thecentral panels34,44 is respectively surrounded by an upwardly or outwardly flaringfrustoconical sidewall35,45, from the upper end of which extends a radially outwardly extendingperipheral flange36,46. The respectivecentral panels34,44, flaringsidewalls35,45 and theperipheral flanges36,46 are respectively parallel to each other. One of the mutually contacting surfaces of the sidewalls has a groovedscrewthread47 and the other of the mutually contacting surfaces of the sidewalls has aslider37 adapted to be received and guided in thegrooved screwthread47. Thescrewthread47 andslider37 have a dual function. One function is to guide angular movement of one disc relative to the other disc and the other function is to separate one disc relative to another disc to break contact between the protrudinglip39 and thecentral panel44 of the facing valve member. Other guiding means may be provided instead of the screwthread groove and slider permitting both of these functions. Alternatively, the axial displacement function can be eliminated and a circular groove used in which case there is simply rubbing contact between the raised lips orbeads39,40 and the facing central panel of the other valve member when the valve member is rotative. In fact, both of these functions may be eliminated, such as disclosed in the third embodiment described below and illustrated inFIG. 12.
• Aperipheral flange46 extends downwardly from theperipheral flange46 of theupper valve member42 and has a radially inwardly projecting hookingmember49 cooperable with the undersurface of at least one of the peripheral flanges of the vessel and fixed valve member and as shown under the undersurface ofperipheral flange26 of thevessel20. Theperipheral flange46 and the adjoiningperipheral sidewall46A have a plurality of spacedcutouts50, afirst portion50A of each cutout having radially inwardly flaringsides50B being located in the peripheral flange and asecond portion50C extending downwardly along theperipheral sidewall46A and defined by leading and laggingparallel edges50D,50E generally in alignment with the respective hookingmembers49.
• The outerperipheral edge36A of theperipheral flange36 of the lower valve member has one ormore protrusions36B defined by a generally radial edge and generally circumferential or tangent edge and twosuch protrusions36B diametrically opposed and mirror images of each other, as shown. The protrusions are adapted to clickingly clear the respective leading edges of thesecond portions50D of thecutouts50 to provide an audible signal that the closed position of the closure member has been reached (seeFIG. 7).
• The lower and upper disc-shapedvalve members32,42, may be assembled in the following manner. Theupper valve member42 is positioned on top of thelower valve member32 previously ultrasonically welded to the vessel, and pressed downwardly. Theedge36A of theperipheral flange36 will ride along and clear theoblique undersurfaces49A of the hookingmembers49 and snap into thespace49C between the upper end surface of the hookingmember49 and the underside ofperipheral sidewall46A of theupper valve member42. The outer diameter of theperipheral flange36 of the lower valve member and theperipheral flange26 of the vessel is slightly greater than the diametrical distance between the radially inner ends49B of the hookingmembers49 thereby preventing the escape of the outer valve member off of the peripheral flange of the vessel.
• Thelower valve member32 may be made of the same polycarbonate or better polystyrene used for the vessel body or some other medical grade material compatible for ultrasonic welding with the peripheral flange of the vessel. The upper valve member is preferably made of a softer material than the material used for the lower valve member in order to enhance the sealing action of the contour lip or bead. For example, a polypropylene available from Huntsman Corp. under reference 13G9A is suitable. Such a polypropylene has a permeability of about 60 cm³×cm/m²×24 hr×atm. at standard temperature and pressure.
• The outer surface of the vessel body has a radially outwardly openingannular groove27 for accommodating a sealingmember28 which may be a O-ring, as illustrated inFIGS. 1 and 2. When the vessel is received in theshell61, the sealingmember28 is in sealing engagement with the intermediate, bight portion of thegroove27 and theinner wall surface67 of theshell61 in alignment therewith. The sealing member in the illustrated embodiment has various features, the most important of which is its high CO₂permeability and CO₂flow rates permitting the inflow of CO₂enriched air from a surrounding CO₂enriched environment. The CO₂inflow rate should enable the CO₂level in the buffer chamber to reach the level in the surrounding CO₂environment in less than about eight hours and preferably in less than about three hours. The flow rate should not be too high so as to cause a significant outflow of the CO₂enriched gas from the buffer chamber in less than two hours. Another advantageous feature of the sealing member is its permeability to O₂to enable the depleted levels of O₂in the CO₂enriched environment to replace the normal level of O₂in the ambient air after the container assembly is placed in the CO₂enriched and O₂lean environment. In practice, the sealing member will be air permeable and therefore allows the in and outflow of all gases in the ambient air, especially N₂, CO₂and O₂. Another advantageous feature of the sealing member is to define a barrier to liquids or viscous substances and in particular vaginal secretions when the container assembly is intended for intravaginal use. Another advantageous feature of the sealing member is to define a barrier against the entry of bacteria and even viruses present in a vagina when the container assembly is to be used intravaginally. Such a sealing member effective against the ingress of vaginal secretions, bacteria and viruses will prevent their entry into the buffer chamber and avoid possible contamination of the contents of the vessel via the vessel walls. A suitable material having all foregoing features is a medical grade silicone which has a very high permeability of the order of 30,500 cm³×cm/m²×24 hr×atm. at standard temperature and pressure. Such an example is, however, not intended to be limiting. The CO₂permeability of the seal may be very much less than that of medical grade silicone and even low as about 0.45 cm³×cm/m²×24 hr×atm. at standard temperature and pressure in the case of a nylon 6.6 gasket. Whatever the seal material is selected, it should enable equilibration between CO₂level in the CO₂enriched environment of the vagina or other incubator and that of the buffer chamber in less than about eight hours and preferably in about three hours.
• The shell is made of a medical grade material having good clarity for inspection of the contents in the microchamber through the wall of the shell. To this end, it preferably has diametrically opposed planar zones of optical quality adapted to be in alignment with the sidewalls of the microchamber (this feature not being shown in the embodiment ofFIGS. 1-8 but designated65 in the embodiment ofFIGS. 9 and 10). A suitable material for the shell is PETG such as Eastar MN058 available from Eastman Chemical Co. having a permeability of about 83 cm³×cm/m²×24 hr×atm. at standard temperature and pressure. Alternatively, polycarbonate but preferably crystal polystyrene may be used for the shell wall. When polycarbonate or crystal polystyrene is also used for the vessel wall, the thickness of the shell wall should be at least about twice the thickness of the vessel wall to ensure that the CO₂flow rate through the vessel wall will be substantially greater than the CO₂flow rate through the shell. The shell may alternatively be made of a material having a substantially nil CO₂permeability such as, for example, glass having suitable mechanical properties. When a shell of nil or very low permeability is employed, obviously essentially all CO₂and/or O₂flow will be through the seal between the vessel wall and the shell wall.
• According to an embodiment, the CO₂permeability of the seal is selected to be, say, one or two orders of magnitude greater than the permeability of the vessel wall and at least two orders of magnitude greater than the CO₂permeability of the shell wall. An example of such an embodiment is a silicone seal having a CO₂permeability of the order of about 30,500 cm³×cm/m²×24 hr×atm. at standard temperature and pressure, a vessel made of Makrolon polycarbonate having a CO₂permeability of about 43.0 cm³×cm/m²×24 hr×atm. at standard temperature and pressure and a shell made of Eastar PETG having a permeability of about 83 cm³×cm/m²×24 hr×atm. at standard temperature and pressure. Preferably, however, the shell is made of medical grade polystyrene having a permeability of about 69 cm³×cm/m²×24 hr×atm. at standard temperature and pressure.
• Preferably, the CO₂permeability of the constituent materials is selected so that the CO₂permeable seal is between about 10,000 and about 40,000 cm³×cm/m²×24 hr×atm. at standard temperature and pressure whereas the CO₂permeability of the vessel is between about 50 to about 500 cm³×cm/m²×24 hr×atm. and the CO₂permeability of the shell is between 0 (corresponding to glass) and 200 cm³×cm/m²×24 hr×atm.
• The vessel and/or the seal material may be also chosen in order to slightly delay the entry of the CO₂enriched gas into the vessel to counter the initial generation of acidic metabolic products during which the CO₂in the vessel which should be allowed to permeate through the vessel wall into the buffer chamber maintaining the desired equilibration level, while thereafter allowing the CO₂enriched environment to flow into the vessel in order to maintain a pH of about 7.4 once acidic metabolic products cease to be produced.
• When the container assembly is not intended for intravaginal use, there may be no need to prevent the ingress of liquids or other viscous fluids.
• Sealing member configurations other than O-rings may be useful and in particular annular gaskets having a rectangular cross section and therefore the same gas flow rate through the entire radial extent of the cross section.
• In practice, the sealing member will have an inner diameter in its rest configuration which is slightly less than the corresponding outer diameter of the complementary bight portion of the groove and an outer diameter which is slightly greater than the inner surface of the shell in contact to cause elastic deformation and thereby ensure a snug fit and satisfactory tightness.
• Thelower end29 of thevessel20 that is the trapezoidal shaped portion (as shown) of the vessel situated below themicrochamber22 will in practice be solid and not hollow. Thelower end29 of the vessel has a locatingmember29A cooperable with a complementary locatingmember63 of hollow cylindrical configuration and upstanding from the bottom62 of theshell61 in the illustrated embodiment. The locatingmember29A has at least one protruding bead orboss29B which is cooperable with a complementary groove orrecess64, so as to define a stable position of the vessel when the vessel is fully inserted into the buffer chamber. Alternatively, or in combination with theaforesaid locating members29A,63, the abutting surfaces of the top edge of the locatingmember63 and the downwardly facing annular shoulder of thelower end29 may define the fully inserted position of the vessel relative to theshell61.
• Guiding members (not illustrated in this embodiment) may be provided to guide the movement of the vessel to ensure the locatingmember29A at thelower end29 is correctly engaged into the complementary locatingmember63. Such guiding members may for example comprise two or more fin-like elements integral with the outer wall of the vessel or the inner wall of the shell and cooperable with the other of the outer wall of the vessel or the inner wall of the shell. Such guiding members are described and illustrated below in connection with the fourth embodiment.
• Such a container assembly as illustrated inFIGS. 1 and 2 may be filled with a suitable biological medium, such as INRA Menoza B2 medium available from Laboratoire CCD in Paris, or Complete P1® Medium with SSS™, ref. 9926, available from Irvine Scientific, Santa Ana, Calif. or any other suitable biological medium for sustaining fertilization of gametes and/or embryo development for up to about three days, whereupon the gametes, namely sperm and oocytes may be introduced in that order through the orifices at least partly in registry to enable the insertion of a catheter or pipette into the main chamber of the vessel while minimizing the size of the open access area. Thereafter, the catheter or pipette is taken out and the closure device is immediately closed, sealing off the interior of the vessel from the environment. Theshell61 is preferably positioned with respect to the vessel prior to filling and loading of gametes. It is then suitable for incubation at about 37° C. in a conventional incubator with a CO₂enriched environment in which case the main function of the sealing member will be to ensure the build-up of CO₂enriched environment in the buffer chamber and which after removal of the container assembly from the incubator will serve as a reservoir for CO₂enriched air to mediate the aqueous pH level inside the vessel.
• This assembly, however, is especially designed for use in intravaginal incubation. To this end, it will be preferably enveloped in a container sleeve orcarrier70 for facilitating intravaginal residence in the posterior fornix. Thecontainer sleeve70 is made of a soft smooth elastic biocompatible material. In the illustrated embodiment, thesleeve70 is of one-piece construction with anapertured sidewall71 extending between opposed rounded ends72,73 suitable for cooperation with the vaginal vault. The lowerrounded end73 has on its outside surface a plurality of circumferentially spaceddimples76 for facilitating the removal of the entire container assembly by means of forceps cooperating with dimples. The upper portion of the lower rounded end converges inwardly (in the rest condition) in order to enhance the elastic engagement with the bottom end of theshell61. Thesidewall71 comprises in practice a plurality, here two, circumferentially spacedlongitudinal straps74 definingapertures75 therebetween. At least one of theapertures75 is suitable for the introduction of the container assembly into theinternal space76 of thecontainer sleeve70. In the embodiment illustrated, the upperrounded end72 is larger than the lowerrounded end73 and comprises aplug portion77 complementary in shape and adapted to be received in the recess defined by thesidewalls45 andcentral panel44 of theupper valve member42. One or both of thestraps74 may have one or more radially inwardly protrudinglip79 cooperable with the outer edge of the lower valve member and/orperipheral flange26 of the vessel. Similarly, the inner surface of the bottomrounded end73 is generally complementary to the bottom wall of theshell61. In the relaxed position of thecontainer sleeve70, that is before it is fitted on thecontainer assembly10, the distance between the inner face of theplug portion77 of the upper rounded end and the inner or the lower face of the lower rounded end of the container sleeve is less than the distance between the outer surface of thebottom wall62 of the shell and the outer surface of thecentral panel44 of the upper valve member, so that an axial biasing force is exerted by thecontainer sleeve70 in order to urge the inner and outer valve members into contact and define a second tier sealing between the interior of the vessel and the surrounding environment. In practice, the total length of the entire container assembly with the container sleeve will be about 4-5 cm for a woman or about 5-15 cm for a cow. The container sleeve may be made of any medical grade thermoplastic elastomer, such as AES Santoprene 8281-35 W237 having a hardness of 35 Shore A and good cushioning properties. Santoprene has a CO₂permeability of about 30-300 cm³×cm/m²×24 hr×atm. at standard temperature and pressure.
• After thecontainer assembly10 is closed with the sleeve fitted thereon, it may be introduced into the vaginal vault and positioned in the posterior fornix for about 48 to about 72 hours according to current procedure. Prior to introduction into the vaginal vault, the container assembly may undergo pre-incubation at 37° C. with or without the sleeve for less than about two hours, safely in a conventional incubator without a CO₂enriched environment. Alternatively, the whole incubation period may be carried out in an artificial CO₂enriched environment.
• When the container assembly is lodged in the posterior fornix, the longitudinal axis of the vessel will be generally horizontal. As the inner wall surface slopes away from the microchamber and towards the closure device, gametes and in particular oocytes will tend to congregate in the vicinity of the zone where the undersurface of the central panel of the lower valve member meets the inner wall surface of the vessel, as illustrated inFIG. 8A, as this will be the lowest level of any part of the combined main and micro chambers when the container assembly is lodged in the posterior fornix. This arrangement is advantageous for enhancing the potential of contact between sperm and oocytes. In a variant (not illustrated), the inner wall surface of the vessel may have its largest dimension intermediate the upper and lower ends of the main chamber, for example by adopting a double frustoconical the sidewall surface joined at their large bases. This variant arrangement, as well as other possible arrangements may assist the congregating of the gametes in a limited zone of the main chamber to enhance the potential for fertilization of oocytes.
• After intravaginal residence, the container assembly is removed. For this purpose, a monofilament string (not shown) of biocompatible material may be attached, bonded to, or integrally formed with, one of the ends or the straps of the container sleeve.
• The container assembly is then taken out of the container sleeve. The contents of the microchamber where the embryo(s) will settle by gravity (in theFIG. 1 position) may then be inspected through one of the opposed sidewalls24 of the microchamber in a recumbent or upright position. Theshell61 has corresponding alignedparallel surfaces65 of optical quality aligned with theopposed sidewalls24, in order not to interfere with the inspection of the embryo(s) which will normally be carried out with a laboratory microscope.
• Once the desired embryo(s) have been selected, an implantation catheter such as Frydman or Wallace catheter is introduced after slightly opening the closure device by turning the upper valve member. The catheter is then snaked through the main chamber to a location proximate the junction of the main chamber and the microchamber which is equipped with anabutment22A in a wall of the microchamber, and in practice a pair of abutments in the opposed sidewalls for docking the end of the catheter at a sufficient height above thefloor22B of the microchamber to prevent the catheter from coming into direct contact and thereby possibly crushing or otherwise injuring the embryo(s) in the microchamber (seeFIG. 1A) As illustrated, the docking abutment(s) is located midway across the opposed sidewalls24 of the microchamber so that the microchamber is aspirated to either side. Alternatively, the docking abutment may be located to one side or the other of the microchamber as disclosed in Ranoux et al. U.S. Pat. No. 6,050,935. The desired embryo(s) may then be aspirated into the catheter and inspected as it or they are drawn upwardly. Indeed, for that purpose, a portion of therecess22C defining theabutment22A also defines aninterior lens face22D. The outer surface of the vessel proximate to the junction of the main chamber and microchamber has anexterior lens face22E in optical alignment with theinterior lens face22D. The lens on one or both sides of the microchamber may be used for viewing the one or more embryo(s) in the catheter during or after the retrieval from the microchamber.
• The embryo(s) may then be implanted in accordance with current IVC practice.
• Another embodiment is illustrated inFIGS. 9 and 10. This second embodiment is suitable for the same purposes as the first embodiment and is of particular interest when the container assembly with its gamete(s) and/or embryo(s) are to be stored for a prolonged period, for example to enable the contents to be shipped prior to implantation. Indeed, in this embodiment, a closure seal is provided between the vessel and the shell and in series with the CO₂permeable sealing member to prevent the egress of the CO₂and/or O₂out of and/or the ingress of gas into the buffer chamber when the container assembly is removed from the vagina or a CO₂enriched incubator.
• Features of the second embodiment corresponding to features of the first embodiment are identified by the same references augmented by “100” and will not again be described.
• In the second embodiment, the upper or outer disc-shaped valve member terminates in theperipheral flange146 which comprises opposed pairs ofradial projections147 alternating with and separated by concave zones. Theradial projections147 alternating and separated by and/or the concave zones facilitate the grasping of the upper disc-shaped valve member for facilitating turning between open and closed positions of the valve. As in the first embodiment, a slider on the upper orouter valve member142 may ride along the screwthread groove in the lower valve member between a position in which theorifices138,148 are out of communication with each other and the solid portions of the central panels134,144 overlying each other and are in mating contact with the contour edges of the orifices. The materials employed in the second embodiment re preferably the same as noted above in connection with the embodiment ofFIGS. 1-8.
• Instead of a single position of the vessel relative to the shell disclosed in the first embodiment, thevessel120 and theshell161 have two stable positions, namely an open position or condition for use when the container assembly is placed in a CO₂enriched environment for incubating the contents and a closed position or condition for sealing the buffer chamber and preventing the escape of the CO₂enriched and O₂depleted contents or the entry of ambient air from the surroundings after the container assembly has been removed from the incubating environment.
• The first position or condition is illustrated inFIG. 9 and the second position or condition illustrated inFIG. 10. TheFIG. 9 position corresponds substantially to theFIG. 2 position of the first embodiment. Thelower end portion129 has a downwardly protruding locatingmember129A selectively cooperable with a complementary corresponding locatingmember163 of hollow cylindrical configuration, as illustrated, and upstanding from the bottom wall162 of theshell161. The locatingmember129A has a pair of axially spaced protruding beads orbosses129B,129C, selectively cooperable with corresponding complementary groove orrecess164. The protrudingbeads129B,129C are located approximately at 90° from each other relative to the general longitudinal axis of thevessel120. Thus, in the first position, the protruding beads orbosses129B come into engagement with the groove orrecess164 and in the second position, the protruding beads orbosses129C come into engagement with the complementary groove orrecess164. To change positions, thevessel120 must be rotated 90° and depressed (or raised) until it reaches the other position.
• In the lower position, aclosure seal180 is defined by theannular notch169 at the upper end of theshell161 which is cooperable with aperipheral portion181 of the undersurface of theperipheral flange126 of the vessel and thefree edge182 of the peripheral flange of the vessel and possibly the free edge of the peripheral flange of thelower valve member132. Theclosure seal180 is essentially defined by the contact between the notch and the portions of the peripheral flange of the vessel. In accordance with a variant, not illustrated, an additional sealing member or gasket may be provided either at the upper end of the shell or at the peripheral flange of the vessel and/or lower valve member. Such an additional sealing member or gasket will be of very low gas permeability to prevent the escape of the atmosphere contained in the buffer chamber or the entry of the ambient atmosphere into the buffer chamber. Such an embodiment is therefore suitable for prolonged storage of many hours, or even days or transit or shipment.
• For such a purpose, the container assembly may be loaded into a pre-heated isothermal holding block for maintaining the contents of the vessel substantially constant at about 37° C. An embodiment of such aholding block100 is illustrated inFIG. 11. The holding block is preferably made of steel, but alternatively may be made of any material having a relatively high level of thermal inertia. As illustrated, the block is parallepipedic with alateral bore101 extending from one side of the block to a point beyond the middle thereof where it is in communication with avertical bore102. Thevertical bore102 extends from the top to the bottom of the block, the lower portion of the bore being of smaller cross section than the upper portion of the bore. Such a preheated isothermal holding block may also be used for temporary storage of a container assembly containing one or more embryos. And to this end,heating block100 may have one or moreadditional bores103.
• Before the holding block is to be used, it is heated to the desired temperature of about 37° C. When the connecting assembly is fully inserted in the lateral bore, the microchamber and thecorresponding surface65 of optical quality on theshell61 will be aligned with thevertical bore102 for viewing the embryo(s) or other contents of the microchamber with a microscope. The part of the container assembly and in particular the microchamber located at the intersection of the lateral and vertical bores is lit from below through a light shaft defined by the lower portion of thevertical bore102.
• Alternatively, the container assembly without the shell may be introduced into the lateral bore for viewing the contents of the microchamber in which case there is no need for the surface(s)65 of optical quality. According to another embodiment (not shown), the block is equipped with a heating element for maintaining the temperature of the block substantially constant at about 37° C. and may be of particular interest for use when the container is to be shipped or transported to another location for inspection of the embryo(s). The top surface of the block also has one or more vertical aligned bores103 for receiving in a substantial vertical position one or more container assemblies prior to inspection or smaller tubes for containing sperm or oocytes.
• Another, third embodiment is illustrated inFIGS. 12-15 which is a variant of the embodiment ofFIGS. 1-8. The features of this third embodiment corresponding to features of the first embodiment are identified by the same references augmented by “200” and will not be described except where necessary to distinguish the third embodiment from the first.
• In the third embodiment, the sealing tightness of the closure device is improved over that of the first embodiment. The third embodiment also includes an optional sealing cap for better impeding the ingress of vaginal fluids in the course of vaginal residence.
• The modifiedclosure device230 comprises avalve231 including two overlying disc-shapedvalve members232,242. One of the disc-shaped valve members is mounted for relative angular movement. As in theFIG. 1 embodiment, the lower disc-shapedvalve member232 is fixed by ultrasonic welding to the upper end of the vessel body and in practice the peripheral flange thereof. As in theFIGS. 1-8, the disc-shaped valve members include acentral panel234,244 having a port ororifice238,248 adapted to be brought into registration in the fully open position of theclosure device230 and out of communication in the fully closed position of the closure device. In this embodiment,orifices238,248 are both preferably of circular contour, as illustrated, though a D-shape member contour may be adapted as in theFIGS. 1-8 embodiment. Preferably, one of the disc-shapedvalve members232,242 has a sealing material affixed to the side of thecentral panel234,244 facing the central panel of the other of the disc-shaped valve members. Preferably, in practice, it is the upper, rotatable disc-shapedvalve member242 that has a liner orlayer239 of sealing material on at least the lower surface thereof facing thecentral panel244 of the lower, fixed disc-shaped valve member. Preferably, both the upper and lower surfaces of the central panel of the upper, rotatable disc-shapedvalve member242 have respective liners or layers239,240 affixed thereto. These liners or layers are advantageously overmolded on the central panel of the disc-shapedvalve member242, but obviously could be bonded or secured with an adhesive. Of course, theorifice248 also extends through the or each of the liners or layers of sealing material. The lower surface of the lower liner orlayer239 is in fluidtight or rubbing contact with the adjacent upper surface of the lower, fixed disc-shaped valve member, thereby enhancing the sealing capability of the closure member in the closed position thereof where the orifices are out of registration of each other. Unlike theFIGS. 1-8 embodiment, the sidewalls between the central panel and the peripheral flanges of the disc-shaped valve members do not have the screwthread groove and complementary slider. Instead, the inner surface of the sidewall of the lower, fixed, rotatable disc-shaped valve members is only frustoconical to a position two thirds the way of the sidewall surface. The uppermost portion of that surface is slightly axially outwardly convergent, so that when the upper disc-shaped valve member must be pressed downwardly upon assembly and is held snugly axially in place by the outwardly tapering upper portion of the sidewall surface of the lower disc-shaped valve member.
• The third embodiment also includes anadditional sealing cap280 which has acentral panel281 which overlies the upper disc-shaped valve member, here rotatable disc-shapedvalve member242, and more particularly the upper layer orliner240 thereon, for sealing engagement thereof.Central panel281 is recessed with an adjoining generallycylindrical sidewall282, adjoining an upperannular flange283 which overlies and is in sealing engagement with the corresponding annular flange of the upper disc-shapedvalve member242 and has aperipheral sidewall284 which extends downwardly overlying the peripheral sidewall246A of the upper disc-shaped valve member and in sealing contact therewith. Thesidewall284 of the sealing cap then extends obliquely (zone285), that is downwardly and radially inwardly towards theshell261 where the cylindricallower part285 of thesidewall284 of the sealing cap comes into sealing engagement with the outer surface of the sidewall of theshell261. In practice, the sealing cap is made of a soft and pliable sealing material, such as medical grade silicone; After the closure device has been brought to its closed position, the sealingcap280 can be pushed or pulled down over theclosure device230 and the outer surface of the upper part of the shell sidewall. The elasticity and slightly smaller dimensions of the souple sealing cap compared with the corresponding dimensions of the closure device and shell sidewall ensure fluidtightness once the sealing cap is in place on the closure device and on the upper part of the shell sidewall.
• The container sleeve270 is fitted over the sealing cap and the shell before introduction into the vagina, substantially as described above, in connection withFIGS. 1-8 embodiment.
• As illustrated inFIG. 15, abutment means are provided to limit the angular movement of the rotatable disc-shapedvalve member242 relative to the fixed disc-shapedvalve member232. In practice, a pair of diametrically opposed protuberances or abutments248 (only one of which is illustrated) are provided at the periphery of the flange of the fixed disc-shapedvalve member232. The inner surface of thelongitudinally extending tabs249B for at least one of the hookingmembers249 has a protruding rib orcomplementary abutment249C longitudinally extending along the full height of thetab249B to the hooking portion which projects obliquely and inwardly to be received under the peripheral flange of the vessel. One of the opposedprotuberances248 is in contact with the protrudingrib249C to define the fully open position of the closure device and the other opposed protuberances (not shown) is in contact to define the fully closed position.
• The fourth embodiment illustrated inFIGS. 16-19 will now be described. It relates to ashell361 which defines abuffer chamber360 for CO₂enriched air surrounding the vessel including its closure device. The vessel and closure device illustrated in this embodiment are those of the third embodiment illustrated inFIGS. 12, 14 and15 but does not include a sealing cap for preventing any ingress of vaginal fluids which is unnecessary in the fourth embodiment as will be understood hereinafter. Theshell361 of the fourth embodiment can be used with other designs of vessels for accommodating biological medium, gametes and/or one or more embryo(s). Regardless of the design, such vessels must have a CO₂permeable wall or walls.
• Thenovel shell361 of fourth embodiment comprises at least twoshell parts363,364. Agas flow passage362 is defined between an outer upper wall of thelower shell part364 and an inner lower wall of theupper shell part363, the inner lower wall ofupper shell part363 having a diameter slightly greater than the diameter of the outer upper wall of thelower shell364. As illustrated, this gas flow passage is annular. It is understood that other forms may be adopted including a plurality of distinct longitudinal grooves. Thegas flow passage362 has a so-called downstream end in communication with thebuffer chamber360 which, in this embodiment, virtually surrounds the entire vessel including its closure device, unlike theFIG. 1 embodiment where the buffer chamber does not also extend around the uppermost end of the vessel body and the closure device. The so-called upstream end of the gas flow passage is defined between an upwardly facingannular shoulder366 on thelower shell part364 and a downwardly facingfree edge367 of theupper shell part363. A CO₂permeable seal or gasket, and preferably an O-ring328 made for example of silicone is located between the inner wall surface of the shell and the outer wall of the vessel. The constituent material has the same properties and is selected for the same reasons as the CO₂permeable O-ring discussed above in connection with the first embodiment. Thus, the CO₂permeable seal365 is preferably not only of relatively high CO₂permeability but also prevents the ingress of vaginal fluids including vaginal secretions into the buffer chamber and into contact with the vessel or its closure device. Similarly, the features and properties of the other main components, and in particular the CO₂permeability of the vessel and the shell are the same and are selected for the same reasons as discussed above.
• The shell parts have coupling means370 comprising agroove370A in the inner wall surface of theupper shell part363 including alongitudinal portion371 extending from thefree edge367 of the upper shell part to acircumferential portion372 extending in the counterclockwise as illustrated. Short of theendwall375 of the circumferential portion of thegroove370A is alongitudinally extending bump374. In practice, there are at least two, and preferably three, such grooves. The circumferential portion defines a central angle of about 30°. A corresponding number ofradial projections377 are provided proximate to the free upper edge of the lower shell part364 (seeFIG. 16).
• In the illustrated embodiment, the CO₂permeable seal is located at the interface between the upper and lower shell parts. According to an alternative embodiment which is not illustrated, the upper and/or lower shell parts may be provided with one or more CO₂permeable members located for example along part of the circumference of the necked or smaller diameter cylindrical portion of the lower shell member or in the central area of the domed portion of the upper shell member. These portions will be in sealing engagement with the surrounding portions of the lower or upper shell members but allow CO₂to permeate into the buffer chamber when the shell is in communication with a CO₂enriched atmosphere. Similarly, the upper or lower shell parts may have rigid transparent or non-transparent zones of plastic materials having different CO₂permeabilities. In this case, the portion or portions of the lower CO₂permeable material may be overmolded around the round portions of higher CO₂permeability.
• After the vessel is loaded with a biological medium, ovocytes and sperm, and/or one or more embryos when used for storage purposes, the closure device is brought to the fully closed position, thus sealing the vessel. The lower end of the vessel has a locatingmember229 which is adapted to be received in a locatingsocket380 on the bottom wall of thelower shell part364. In this embodiment, the locatingmember229 is received with clearance in the locatingsocket380. If the clearance is sufficiently ample, the locatingsocket380 does not ensure an stable upright position of the vessel on their own. In this case, the coaxial position of the vessel relative to thelower shell part364 is ensured by guiding means on the vessel or a part appurtenant thereto and inner wall of the lower shell part. To this end in the illustrated embodiment the longitudinally extending guidingmembers381 are provided on the inside wall of the lower part of the shell which are cooperable with a ring, and in particular an O-ring338 as illustrated, received in an outwardly openinggroove227 on the side wall of the vessel. It will be understood that the function of O-ring338 is not the same of that of the O-ring238. Indeed, the O-ring338 needs not to have a particular permeability or be able to impede the ingress of vaginal fluids, for example. The outer diameter of the ring is preferably slightly greater than the diameter defined by the guidingmembers381 at the same location thereby ensuring in cooperation with the complementary locating member and locating socket a stable coaxial position. Thanks the resilience of the O-ring and the loose fit of the complementary locating members; some movement of the vessel relative to the shell is possible. Alternatively, a more rigid coaxial positioning of the vessel relative to the shell is possible in which case the O-ring may be either of less resilient material or replaced by a openable rigid ring or even a fixed or integrally molded with the vessel itself. The guidingmembers381 are circumferentially spaced from each other and are preferably L-shaped in cross section for receiving a label (not shown) for identifying the person to whom the oocytes or embryo(s) belong.
• For assembling theshell parts363,364 they are moved towards each other initially longitudinally, guided by the cooperation of theradial projections377 and thelongitudinal portions371 of thegrooves370A. Additional longitudinal force is exerted to compress the CO₂seal gasket slightly whereupon theradial projections377 may enter the respective circumferential portions, and the shell parts may then be turned relative to one another until theradial projections372 move beyond thebumps374 in the circumferential portions. The circumferential outer surface of theradial projections377 ride onto thebumps374, as the radial projections reach theendwalls375 of thecircumferential portions372 of thegroove370A, thus tightening the engagement between the shell parts and thereby resisting inadvertent relative angular movement once the shell is closed, and also in the course of vaginal residence.
• Each of theshell parts363,364, is made of molded rigid, transparent medical grade biocompatible material such as a crystal polystyrene and in particular Nova High Heat Crystal Polystyrene, ref. 1204, available from Nova Chemicals, Moon Township, Pennsylvania though polycarbonate may also be suitable. The polystyrene will have a highly smooth or “polished”, surface finish which has been found to be highly suitable for the about 48-72 hours contact with vaginal tissue of the posterior fornix with a reduced risk of irritation than with the Santoprene container sleeve or carrier of the type illustrated inFIG. 8 or12 and/or the silicone sealing cap.
• The sidewall of thelower shell part364 has a substantially cylindrical wall portion between upwardly and downwardly flaring portions. The cylindrical wall portion of reduced diameter facilitates the manual or mechanical gripping of the shell, for example, with a tenaculum. The total length of the shell is preferably 40-50 mm and the transverse dimension of the cylindrical wall of smaller diameter is preferably 20-25 mm in the case of a shell intended for a woman's vagina.
• The sidewall of thelower shell part364 may be provided with a portion or portions of optical quality (not shown) permitting the viewing of embryos settled in the microchamber of the vessel.
• According to a non-illustrated feature, once the container assembly is removed from the vagina, the CO₂permeable seal is inhibited or overridden, for example by positioning or placing over the CO₂permeable seal, a complementary sealing ring of low CO₂permeability, e.g. of low permeability nylon, over the CO₂permeable seal, or simply at the upstream end of the gas flow passage between the upper and lower shell parts, so as to seal off or substantially seal off the gas flow passage connecting the buffer chamber to the surroundings, and thereby reduce or eliminate the loss of the CO₂enriched air and/or O₂depleted atmosphere from the buffer chamber. With such a sealing ring in place, the shell can be used for storage or transit of the embryo(s) prior to retrieval and transfer. Alternatively, other kinds of seal may be provided at the gas flow passage, for example a high seal CO₂permeable tape with a suitable adhesive affixing it to the outer surface of the upper and lower shell parts. In the latter case, theannular shoulder366 of the lower shell part may be followed by a cylindrical portion substantially of the same diameter as the outer surface of the lower portion or skirt of the upper shell part. Similarly, an adhesive tape can carry on its adhesive face a low CO₂permeability sealing ring adapted to close off or substantially close off the gas flow passage.
• In any event after incubation the vessel with or without the shell may be transferred to an isothermal insulating block illustrated inFIG. 11 for examination and selection of the embryos before the transfer via catheter as described above
• It would be appreciated that these and other modifications and variants may be adopted without departing from the spirit and scope of the invention defined by the appended claims.

Claims (60)

1. A container assembly comprising (i) a vessel for containing a biological medium, gametes and/or one or more embryo (s), the vessel having a C0₂permeable wall; (ii) a closure device for selective access to the interior of the vessel, and (iii) a buffer chamber for a C0₂enriched atmosphere cooperable with the vessel and in communication with the C0₂permeable wall.

2. A container assembly according toclaim 1, wherein the buffer chamber has an open condition for communication with a C0₂enriched environment and a closed condition for closing off the chamber from the surroundings.

3. A container assembly according toclaim 1, further comprising a C0₂permeable seal for impeding the ingress of liquids into the buffer chamber while allowing the entry of CO₂.

4. A container assembly according toclaim 1, wherein the buffer chamber is defined by a shell disposed at least partly around the vessel.

5. A container assembly according toclaim 4, wherein the buffer chamber is defined by a shell disposed at least partly around the vessel and wherein said shell is mounted relative to the vessel for movement between an open position and a closed position corresponding to the respective open and closed conditions.

6. A container assembly according toclaim 5, further comprising a fluid tight seal operatively disposed between the vessel and the shell to prevent ingress and egress of fluids to and from the buffer chamber in the closed position.

7. A container assembly according toclaim 1, wherein the vessel comprises a main chamber and a microchamber for communication of the biological medium, gametes and/or one or more embryo (s) therebetween, the microchamber and at least part of the main chamber being surrounded by the buffer chamber and the C0₂permeable wall including a wall defining the microchamber.

8. A container assembly according toclaim 1, wherein substantially the entire vessel wall is C0₂permeable.

9. A container assembly according toclaim 1, wherein the buffer chamber has a lower C0₂outflow rate than the C0₂inflow rate of the vessel.

10. A container assembly according toclaim 1, wherein the buffer chamber ensures C0₂equilibration after removal of the container assembly from a C0₂enriched environment.

11. A container assembly according toclaim 3, for use in intravaginal fertilization and culture, wherein the C0₂permeable seal is operatively disposed between the buffer chamber and the surroundings for impeding the ingress of vaginal fluids into the buffer chamber while allowing the entry of the C0₂enriched gas.

12. The container assembly according toclaim 3, wherein the CO₂permeable seal is readily replaceable with another seal having a different C0₂permeable inflow rate.

13. The container assembly according toclaim 1, wherein the closure device comprises a valve including disc-shaped members in overlying relationship mounted for relative angular movement.

14. The container assembly according toclaim 13, wherein an inner one of the disc-shaped members is fixed relative to the vessel and an outer one of the disc-shaped members is mounted for angular movement.

15. The container assembly according toclaim 14, wherein each of the disc-shaped members has an orifice in a central panel for introducing a catheter or pipette for gametes and/or one or more embryo (s), an upstanding sidewall around the central panel and a peripheral flange extending radially outwardly from the sidewall.

16. The container assembly according toclaim 1, wherein the vessel comprises a main chamber and a microchamber for the flow of the biological medium and movement of gametes and/or embryos therebetween, the inner wall surface of the main chamber member tapering from an end fitted with the closure device, towards the microchamber.

17. The container assembly according toclaim 16, wherein an upper part of the vessel has an upwardly flaring sidewall and a peripheral flange extending outwardly therefrom, the sidewalls of the disc-shaped members being nested in the upwardly flaring sidewall of the vessel, and the peripheral flanges of disc-shaped members extending parallel to the peripheral flange of the vessel.

18. The container assembly according toclaim 15, wherein a liner of sealing material is affixed to the central panel of one of the disc-shaped members.

19. The container assembly according toclaim 15, wherein one of the disc-shaped members has a protruding lip along an edge defining an orifice therein, the lip facing the other of the disc-shaped members of the valve and sealingly engageable therewith.

20. The container assembly according toclaim 19, wherein said one of the disc-shaped members has a raised portion of substantially the same height of the protruding lip and spaced therefrom for maintaining the central panels parallel to each other.

21. The container assembly according toclaim 15, wherein the peripheral flange of upper one of the disc-shaped members has a peripheral sidewall radially outwardly beyond the peripheral flange of a lower one of the disc-shaped members and the peripheral flange of the lower disc-shaped member, the peripheral flange of the lower disc-shaped members having protrusions selectively cooperable with cutouts in the peripheral sidewall in a closed position of the closure device.

22. The container assembly according toclaim 15, wherein the peripheral sidewall of the upper disc-shaped member has one or more hooking members for snap-fitting axial retention of the upper disc-shaped member on the lower disc-shaped member.

23. The container assembly according toclaim 5, wherein an upper edge of the shell is in sealing engagement with a radially outwardly extending flange at an upper end of the vessel in the closed position of the buffer chamber.

24. The container assembly according toclaim 5, wherein said shell has an upstanding locating member on a bottom wall thereof and the vessel has a protruding complementary locating member at the lower end thereof.

25. The container assembly according toclaim 24, wherein the vessel in the open condition of the buffer chamber is angular offset from the vessel in the closed condition of the buffer chamber.

26. The container assembly according toclaim 5, wherein a locating member and complementary locating member define two locating positions corresponding respectively to the open and closed positions of the shell, a portion of a lower end part of the vessel being in engagement with the complementary locating member in a first locating position, a portion of the lower end part of the vessel extending beyond the upper part of the complementary locating member in the second locating position.

27. The container assembly according toclaim 26, wherein the locating member and complementary locating member have respective cooperable detent means for defining said first and second locating positions.

28. The container according toclaim 1, wherein the buffer chamber comprises a shell having a marking surface on an external wall for patient identification.

29. The container assembly according toclaim 1, wherein the vessel and closure device define an intravaginal container for intravaginal incubation, and further comprising a container sleeve with opposed rounded ends suitable for cooperation with a vaginal vault, the rounded ends having inner faces cooperable with opposed ends of the container, and an elastic sidewall connecting the rounded ends and urging the inner faces towards each other when the container is received in the sleeve.

30. The intravaginal incubation container assembly according toclaim 29, wherein the elastic sidewall has one or more openings for introduction and removal of the intravaginal container.

31. The intravaginal incubation container assembly according toclaim 29, wherein an inner face of one of the sleeve ends has a plug engageable in and mating with a central recess defined by the closure member for urging elements of a closure member towards each store.

32. The container assembly according toclaim 7, wherein the microchamber has opposed walls of suitable quality for viewing the contents of the microchamber under magnification, an abutment being provided on an inner surface of one or both of the opposed walls for docking a catheter, substantially at the middle of the opposed walls.

33. The container assembly according toclaim 32, wherein the abutment is a part of a recess in the one of the opposed walls of the microchamber.

34. The container assembly according toclaim 33, wherein a portion of the recess in the one of the opposed walls of the microchamber defines an interior lens face and the outer surface of the vessel proximate to a junction of the main chamber and the microchamber and in viewing alignment with the interior lens face comprising an exterior lens face, a lens thus defined by the lens faces being located for viewing one or more embryos in a catheter during or after retrieval from the microchamber.

35. The container assembly according toclaim 32, wherein a portion of the opposed walls of the microchamber and a portion of the main chamber proximate to a junction of the main chamber and the microchamber define an interior lens face in viewing alignment with an exterior lens face, the lens thus defined by the lens faces being located for viewing one or more embryos in the catheter during or after retrieval from the microchamber.

36. The container assembly according toclaim 35, wherein the zones adjoining internal walls and a floor of the microchamber include an inclined portion for opposing the formation of fluid vortexes.

37. The container assembly according toclaim 7, wherein, the inner wall surface of the main chamber is generally frustoconical and includes a small end section adjoining and merging into the microchamber, the microchamber being of generally rectangular cross section, the configuration of the inner wall surface of the main chamber favoring the flow of biological medium therebetween.

38. The container assembly according toclaim 1, wherein said buffer chamber mitigates temperature changes inside the vessel when the container assembly is removed from a C0₂enriched environment at a temperature of about 37° C.

39. The container assembly according toclaim 6, wherein the fluidtight seal operatively disposed between the vessel and the shell in a closed position of the shell is adapted to prevent inflow of the atmosphere of

the surroundings after removal from a temperature controlled C0₂enriched environment and/or outflow of C0₂enriched atmosphere from the buffer chamber.

40. The container assembly according toclaim 6, wherein the fluidtight seal operatively disposed between the vessel and the shell in a closed position of the shell is adapted to prevent inflow of 0₂into the buffer chamber after removal from a temperature controlled 0₂depleted atmosphere.

41. The container assembly according toclaim 4, wherein the shell defining the buffer chamber impedes the loss of gas therefrom, and the shell has a much lower C0₂outflow than the C0₂inflow rate of the vessel wall.

42. The container assembly according toclaim 1, wherein the CO₂permeable seal has a C0₂permeability at least an order of magnitude greater than that of the vessel wall.

43. The container assembly according toclaim 1, wherein the C0₂permeable seal has a C0₂permeability at least two orders of magnitude greater than that of the shell.

44. The container assembly according toclaim 7, wherein the volume of the main chamber is between about 10 and about 100 ml, and the volume of the microchamber is between about 0.4 and about 1.5 ml.

45. The container assembly according toclaim 21, wherein the at least radial protrusion is adapted to audibly clear an edge of at least one of the cutouts, as the closure device reaches the closed position.

46. The container assembly according toclaim 1, wherein the buffer chamber is defined by a shell surrounding the vessel.

47. The container assembly according toclaim 46, wherein said shell has at least two parts, the shell parts having coupling means for coupling the shell parts in the closed position.

48. The container assembly according toclaim 47, wherein a gas flow passage is defined between respective ones of said at least two shell parts.

49. The container assembly according toclaim 48, wherein a C0₂permeable seal is located in the gas flow passage for allowing the flow of C0₂enriched air from a source of C0₂enriched air into the buffer chamber.

50. The container assembly according toclaim 49, wherein said C0₂permeable seal is adapted to prevent the ingress of vaginal fluids into the buffer chamber.

51. The container assembly according toclaim 47, wherein the CO₂permeable seal is compressed between respective shell parts in the closed position.

52. The container assembly according toclaim 46, wherein the shell has rounded ends and is sized and configured for residence in the posterior fornix.

53. The container assembly according toclaim 46, wherein the shell is made of rigid and transparent biocompatible material.

54. The container assembly according toclaim 46, wherein the shell has a transverse dimension of about 20 mm to about 25 mm and a longitudinal dimension of about 40 mm to about 50 mm.

55. The container assembly according toclaim 47, wherein said coupling means holds the respective shell parts against angular and longitudinal movement in the closed position of the shell.

56. The container assembly according toclaim 55, wherein said coupling means comprises a groove in one of said respective shell parts having a first longitudinal portion followed by a circumferential portion, and the other one of the respective shell parts having a boss shaped for restrained movement in the groove.

57. The container assembly according toclaim 56, wherein the circumferential portion has an endwall cooperable with the boss for defining the closed position of the shell and a bump located in the circumferential portion spaced from the endwall to limit inadvertent relative angular movement of the shell parts from the closed position.

58. The container assembly according toclaim 47, wherein at least one of the shell parts has a label groove along the inside wall of said at least one shell part.

59. The container assembly according toclaim 58, wherein the label groove protrudes inwardly from the inner sidewall of the at least one part of the shell for cooperating with the vessel or an appurtenance thereon for axially aligning the vessel relative to the shell.

60. The container assembly for storage or shipment of gametes and/or at least one embryo according toclaim 1.

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