Sharon W.H. Lee

Vaginal misoprostol compared with oral misoprostol in termination of second-trimester pregnancy

Objective To compare the efficacy of vaginal with oral misoprostol in termination of second-trimester pregnancy after pretreatment with mifepristone. Methods Women requesting termination of secondtrimester pregnancy were randomized into two groups. Thirty-six to 48 hours after oral administration of 200 mg of mifepristone, women were given either oral or vaginal misoprostol 200 μg every 3 hours for a maximum of five doses in the first 24 hours. Women receiving oral misoprostol also were given a vaginal placebo (vitamin B6), whereas those receiving vaginal misoprostol were given an oral placebo. If they failed to abort, a second course was given by the same route. Results The median induction-abortion interval in the vaginal group (9 hours) was significantly shorter than that in the oral group (13 hours). The percentage of women aborting within 24 hours in the vaginal group (90%) was significantly higher than that in the oral group (69%). The median amount of misoprostol used in the vaginal group (600 μg) also was significantly less than that in the oral group (1000 μg). There was no significant difference in the incidence of side effects between the two groups except for fatigue and breast tenderness, which were more common in the oral group. Seventy-six percent of the women preferred the oral route, and 24.5% of the women preferred the vaginal route. Conclusion Vaginal misoprostol is more effective than oral misoprostol in termination of second-trimester pregnancy after pretreatment with mifepristone, but more women preferred the oral route.

Pharmacokinetics of repeated doses of misoprostol

BACKGROUND Misoprostol is widely used in obstetrics and gynaecology for medical abortion, cervical priming and induction of labour. To aid the design of effective and safe regimens, we have investigated the pharmacokinetic parameters after the vaginal or sublingual administration of repeated doses of 400 microg of misoprostol. METHODS Women undergoing termination of pregnancy by suction evacuation were randomized to receive 400 microg of sublingual or vaginal misoprostol every 3 h for five doses. Venous blood was taken at 180, 200, 240, 360, 380, 420, 540, 560, 600, 720, 740, 780 and 900 min after the first dose of misoprostol for determination of the plasma level of misoprostol acid (MPA). RESULTS The peak plasma levels of MPA decreased with successive doses of vaginal misoprostol, whereas the peak plasma levels were similar with successive doses of sublingual misoprostol. After the third dose, the peak plasma levels of MPA after sublingual misoprostol were significantly higher than those after vaginal administration. After the final dose, the area under the MPA concentration-time curve after sublingual administration was significantly higher than that after vaginal misoprostol (P < 0.031). However, subgroup analysis in the vaginal administration group showed that the progressive decline in the peak plasma levels of MPA occurred only in women with significant vaginal bleeding. CONCLUSIONS The peak plasma level of MPA after each dose of misoprostol is higher and the bioavailability is also greater after sublingual administration, compared with that after vaginal administration, of repeated doses of misoprostol. The difference was probably due to the reduction in absorption of vaginal misoprostol in the presence of significant vaginal bleeding.

Pilot study on the use of sublingual misoprostol in termination of pregnancy up to 7 weeks gestation

BACKGROUND This study was conducted to assess the efficacy and incidence of side effects of a regimen of repeated doses of 400 microg sublingual misoprostol for termination of pregnancy of <7 weeks gestation. METHOD Fifty women were given 400 microg sublingual misoprostol every 3 h for three doses. Two additional doses were given if necessary. RESULTS Forty-three women (86%) had a complete abortion. Two women (4%) had incomplete abortion and 5 (10%) had an ongoing pregnancy. The median interval between the first dose of misoprostol and the passage of tissue mass was 14.1 h (3.25-561.6 h). The median duration of vaginal bleeding was 20 days (8-85 days). Side effects were mild and there was no significant drop in hemoglobin level. CONCLUSIONS Our preliminary results on sublingual misoprostol show that it is a promising method for medical termination of pregnancy of <7 weeks. It may be used as an alternative for women who do not want surgical evacuation and who live in an area where mifepristone is not available.

Pilot Study on the Use of a Two-Week Course of Oral Misoprostol in Patients After Termination of Pregnancy With Mifepristone and Misoprostol

Twenty women who requested early first trimester termination of pregnancy were recruited to study the tolerability of a 2-week course of oral misoprostol after termination of pregnancy by mifepristone and vaginal misoprostol. Ten patients (50%) complained of mild diarrhea during the 2-week course of misoprostol. Otherwise, there were no other significant side effects. The 2-week course of misoprostol was well tolerated by women who underwent early first trimester termination of pregnancy with mifepristone and misoprostol.