Misoprostol works as well as [PGF.sub.2[alpha]] for abortion

OB/GYN News, Dec 1, 2002 by Mitchel L. Zoler

BALTIMORE -- Intravaginal misoprostol was as effective for ending second-trimester pregnancies as intraamniotic prostaglandin [F.sub.2[alpha]] in a controlled study with 217 women.

Although intraamniotic prostaglandin [F.sub.2[alpha]] ([PGF.sub.2[alpha]]) has been the standard method for medically induced, second-trimester pregnancy termination, intravaginal infusion of misoprostol has been increasingly used despite little evidence from head-to-head comparisons of the two methods. The results of this study show that intravaginal misoprostol is as effective as the alternative while causing less vomiting, Dr. Hani A. Akoury said while presenting a poster at the annual meeting of the American Society of Human Genetics.

Misoprostol is indicated solely for the prevention of gastric ulcers associated with the use of nonsteroidal anti-inflammatory drugs.

The study involved 217 women at week 15-24 of pregnancy at three university teaching hospitals in Toronto. They were randomized to three treatment groups: Women in one group received an intraamniotic infusion of 40 mg [PGF.sub.2[alpha]] followed 4 hours later by a continuous infusion of oxytocin for 24 hours or until labor began. The women in the second group received 400 [micro]g misoprostol as an intravaginal infusion every 4 hours for 24 hours followed by an oxytocin infusion. Women in the third group received 400 [micro]g misoprostol orally every 4 hours for 24 hours followed by an oxytocin infusion.

The mean time to the start of placental delivery was 18.3 hours among the women treated with intravaginal misoprostol, 21.1 hours among those treated with [PGF.sub.2[alpha]], and 30.5 hours among those treated with oral misoprostol, said Dr. Akoury, an ob.gyn. at Mount Sinai Hospital in Toronto.

The difference in time to placental delivery between intravaginal misoprostol and [PGF.sub.2[alpha]] was not statistically significant, but oral misoprostol was substantially less effective than the other two treatments.

The most common adverse effect of treatment was vomiting, which occurred in 68% of the women treated with [PGF.sub.2[alpha]], 38% of those treated with intravaginal misoprostol, and 23% of those treated with oral misoprostol. Responses on a questionnaire given to all of the women in the study showed that intravaginal misoprostol was preferred over [PGF.sub.2[alpha]].

Although oral misoprostol was not as effective as the other treatments in this study at the dose used, its efficacy may improve if the regimen is altered, such as giving smaller doses more frequently, Dr. Akoury said.