Mid-trimester termination of pregnancy--a randomised controlled trial of two prostaglandin regimens

Abstract

Objective: To determine the more applicable of two ways of prostaglandin induction currently in use in second trimester induced abortions for congenital or chromosomal abnormalities.

Design: A prospective randomised controlled trial.

Setting: Department of Obstetrics and Gynaecology, Tygerberg Hospital, CP.

Study population: Twenty consecutive patients admitted for termination of pregnancy for congenital or chromosomal abnormalities between 14 and 26 weeks' pregnancy duration.

Management: Patients were randomly selected to receive either 1.5 mg prostaglandin E2 (PGE2) gel extra-amniotically or 25 mg prostaglandin F2 alpha (PGF2 alpha) intra-amniotically. Patients in both groups received oxytocin to a maximum dosage of 120 mU per minute if they had not aborted 18 hours after the original administration of either prostaglandin regimen. If abortion had not taken place 36 hours after commencement of treatment, management was considered unsuccessful.

Main outcome measurements: Proportion of successful inductions and complications.

Results: Complications of management were rare and did not differ between the two management groups. However, there were significantly more failures in the group who received intra-amniotic PGF2 alpha (7 v. 2 patients) as well as a significantly higher need for oxytocin in this group (10 v. 4 patients).

Conclusions: With promising drugs such as prostaglandin analogues and anti-progesterones not universally available, methods of induction suitable to the local situation should be sought. Extra-amniotic PGE2 seems more suitable than intra-amniotic PGF2 alpha because of a shorter induction-to-delivery time without increased morbidity.