| Background | |
|---|---|
| Abortion type | Surgical |
| First use | 1934 |
| Last use | Usage has declined in U.S. since the 1970s. |
| Gestation | 16-24 weeks |
| Usage | |
| United States | 0.9% (2003) |
| Infobox references | |
Instillation abortion is a rarely used method oflate-term abortion, performed by injecting a solution into theuterus.
Instillation abortion is performed by injecting achemicalsolution consisting of eithersaline,urea, orprostaglandin through theabdomen and into theamniotic sac. Thecervix isdilated prior to the injection, and the chemical solution inducesuterine contractions which expel thefetus.[1] Sometimes adilation and curettage procedure is necessary to remove any remaining fetal or placenta tissue.[2]
Instillation methods can requirehospitalization for 12 to 48 hours.[2] In one study, whenlaminaria were used to dilate the cervix overnight, the time between injection and completion was reduced from 29 to 14 hours.[3]
The method of instillation abortion was first developed in 1934 byEugen Aburel.[4] It is most frequently used between the 16th and 24th week ofpregnancy, but its rate of use has declined dramatically in recent years.[2] In 1968, abortion by the instillation of saline solution accounted for 28% of those procedures performed legally inSan Francisco, California.[5] Intrauterine instillation (of all kinds) declined from 10.4% of all legal abortions in the U.S. in 1972 to 1.7% in 1985,[6] falling to 0.8% of the total incidence of induced abortion in the United States during 2002,[7] and 0.1% in 2007.[8]
In a 1998Guttmacher Institutesurvey, sent to hospitals inOntario, Canada, 9% of thosehospitals in the province which offered abortion services used saline instillations, 4% used urea, and 25% used prostaglandin.[9] A 1998 study of facilities inNigeria which provide abortion found that only 5% of the total number in the country use saline.[10]
Once in common practice, abortion by intrauterine instillation has fallen out of favor, due to its association with seriousadverse effects and its replacement by procedures which require less time and cause less physical discomfort.[11]
Saline is in general safer and more effective than the other intrauterine solutions because it is likely to work in one dose. Prostaglandin is fast-acting, but often requires a second injection, and carries more side effects, such asnausea,vomiting, anddiarrhea.[2]
Instillation of either saline or prostaglandin is associated with a higher risk of immediate complications than surgicalD&C.[12]Dilation and evacuation is also reported to be safer than instillation methods.[13] One study found that the risk of complications associated with the injection of a combination of urea andprostaglandin into theamniotic fluid was 1.9 times that of D&E.[13]
The rate ofmortality reported in theUnited States between 1972 and 1981 was 9.6 per 100,000 for instillation methods. This is in comparison to rates of 4.9 per 100,000 for D&E and 60 per 100,000 for abortion byhysterotomy andhysterectomy.[13]
There have been at least two documented cases of unsuccessful instillation abortions that resulted in live births.[14][15]
