Comparison between intraamniotic PGF2 alpha and vaginal PGE2 for second-trimester abortion

Two hundred three consecutive patients undergoing second-trimester abortion with either intraamniotic prostaglandin F2 alpha (PGF2 alpha) or vaginal prostaglandin E2 (PGE2) were compared. There were no statistical differences between the 2 groups with regard to age, race, gravidity, or gestational age. The average induction-to-abortion (I-A) interval for PGF2 alpha was 18.53 hours, compared with 13.25 hours for PGE2. The largest difference was in primigravidas (PGE2 6 hours shorter). There was no difference in the frequency of completed abortions in each group (approximately 50%). No correlation was found between gestational age and the I-A interval or percentage of complete abortions. Percentage of abortions completed by 24 hours or less was 97.6% for PGE2, versus 78.5% for PGF2 alpha. Abortions with PGE2 required a larger total prostaglandin dose and a cost 2.8 times greater than did those with PGF2 alpha. Side effects of vomiting, diarrhea, pyrexia, and hypotension were significantly more frequent with PGE2 suppositories. Hypertension was statistically more common with PGF2 alpha. In pregnancy of less than 16 weeks' duration, the known difficulty in performing amniocentesis and the proved shorter I-A interval with PGE2 imply that vaginal suppositories are the agent of choice prior to 16 weeks' gestation.