24 May 2010

Misoprostol to terminate pregnancy in the second or third trimester

The study’s objectives were to compare the benefits and harms of misoprostol to induce labour to terminate pregnancy in the second and third trimester for women with a fetal anomaly or after intrauterine fetal death when compared with other methods of induction of labour. From Cochrane Database of Systematic Reviews

The authors note that a woman may need to give birth prior to the spontaneous onset of labour in situations where the fetus has died in utero (also called a stillbirth), or for the termination of pregnancy where the fetus, if born alive would not survive or would have a permanent handicap. Misoprostol is a prostaglandin medication that can be used to induce labour in these situations.

The study’s objectives were to compare the benefits and harms of misoprostol to induce labour to terminate pregnancy in the second and third trimester for women with a fetal anomaly or after intrauterine fetal death when compared with other methods of induction of labour.

The authors searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (November 2009). The selection criteria were randomised controlled trials comparing misoprostol with placebo or no treatment, or any other method of induction of labour, for women undergoing induction of labour to terminate pregnancy in the second and third trimester following an intrauterine fetal death or for fetal anomalies. Both authors independently assessed trial quality and extracted data.

The authors included 38 studies (3679 women). Nine studies included pregnancies after intrauterine deaths, five studies included termination of pregnancies because of fetal anomalies when the fetus was still alive and the rest (24) presented the pooled data for intrauterine deaths, fetal anomalies and social reasons.When compared with agents that have traditionally been used to induce labour in this setting (for example, gemeprost, prostaglandin E(2) and prostaglandin F(2alpha)), vaginal misoprostol is as effective in ensuring vaginal birth within 24 hours, with a similar induction to birth interval.

Vaginal misoprostol is associated with a reduction in the occurrence of maternal gastrointestinal side effects such as nausea, vomiting and diarrhoea when compared with other prostaglandin preparations. While the different treatments involving various prostaglandin preparations appear comparable for the reported outcomes, the information available regarding rare maternal complications, such as uterine rupture, is limited.

The authors concluded that the use of vaginal misoprostol in the termination of second and third trimester of pregnancy is as effective as other prostaglandin preparations (including cervagem, prostaglandin E(2) and prostaglandin F(2alpha)), and more effective than oral administration of misoprostol. However, important information regarding maternal safety, and in particular the occurrence of rare outcomes such as uterine rupture, remains limited. Future research efforts should be directed towards determining the optimal dose and frequency of administration, with particular attention to standardised reporting of all relevant outcomes and assessment of rare adverse events. Further information is required about the use of sublingual misoprostol in this setting.

School of Paediatrics and Reproductive Health, Discipline of Obstetrics and Gynaecology, The University of Adelaide, Women’s and Children’s Hospital, 72 King William Road, Adelaide, South Australia, Australia, 5006.

Misoprostol for induction of labour to terminate pregnancy in the second or third trimester for women with a fetal anomaly or after intrauterine fetal death. Dodd JM, Crowther CA. Cochrane Database of Systematic Reviews. 2010 Apr 14;4:CD004901.