A prospective randomized double-blind placebo-controlled trial was conducted in 70 subjects to determine whether pre-treatment with misoprostol could facilitate termination of second trimester pregnancy by gemeprost. The women received either 400 micrograms oral misoprostol or placebo tablets 12 hours before the administration of vaginal pessary of gemeprost 1 mg every 3 hours. There were no significant differences in induction-abortion interval and the amount of gemeprost required between the misoprostol and the placebo group. There was no significant difference in the incidence of side effects or analgesic requirement between the two groups. We conclude that oral misoprostol is not useful in facilitating termination of second trimester pregnancy by gemeprost.
PIP: In Hong Kong, 70 healthy women aged 16-40 years at the gestational age of 14-20 weeks who requested legal termination of pregnancy were randomly allocated to receive either 400 mg misoprostol or a placebo (vitamin B6) 12 hours before initial administration of intravaginal gemeprost pessary (1 mg) every three hours. This double-blind study aimed to determine whether pretreatment with oral misoprostol can improve the efficacy of intravaginal gemeprost pessary to effect induced abortion. The two groups responded essentially the same in terms of the incidence of nausea, vomiting, dizziness, fatigue, breast tenderness, or lower abdominal pain during the interval between misoprostol administration and gemeprost administration. Similarly, side effects and analgesic requirements did not differ significantly. The complete abortion rate was not significantly different between the two groups (62.9% for misoprostol and 68.6% for placebo). Even though the induction-abortion interval was shorter and the amount of gemeprost required was smaller in the misoprostol group than the placebo group (27.3 vs. 28.2 hours and 4.9 vs. 5.7 mg, respectively), the differences were not significant (p = 0.0863 and 0.0957, respectively). These findings suggest that oral misoprostol does not facilitate termination of second trimester pregnancy by intravaginal gemeprost pessary.