Early abortion induction by a combination of mifepristone and oral misoprostol: a comparison between two dose regimens of misoprostol and their effect on blood pressure

Abstract

Objectives: 1. To investigate the efficacy of 800 micrograms misoprostol (a PGE1 analogue) when administered to women pretreated with mifepristone for early pregnancy termination. 2. To establish means of minimising gastrointestinal side effects by comparing two different misoprostol regimens. The impact of these regimens on blood pressure was investigated in a subgroup of patients.

Design: A randomised study of 150 women of 56 days gestation, or less, allocated to receive oral misoprostol either in a single dose of 800 micrograms or as two doses of 400 micrograms administered sequentially 2 h apart; in each case misoprostol was administered 36 to 48 h after receiving mifepristone 200 mg orally.

Main outcomes: Complete abortion rates, the frequency and severity (patients' perception) of gastrointestinal side effects, and blood pressure changes in response to prostaglandin administration.

Results: The overall success rate was 93%. Seventy-one (95%) women who received a single dose of misoprostol and sixty-nine (92%) who received the sequential dose aborted completely. There were two ongoing pregnancies in the first group (2.5%) and three (4%) in the second. The overall ongoing pregnancy rate was 3%. The incidence of diarrhoea was significantly lower for women receiving the sequential dose, and no significant differences were found in the incidence of the other gastrointestinal side effects. The only noted significant change in blood pressure was in diastolic pressure 4 h after the administration of the higher dose of prostaglandin, but this was slight.

Conclusions: The combination of mifepristone and oral misoprostol provides an alternative method to inducing abortion of pregnancies of up to eight weeks gestation. Patients receiving the single dose of 800 micrograms were more troubled by diarrhoea than those on the sequential regimen. The ongoing pregnancy rate was higher than previously reported with vaginal or parenteral administration of prostaglandin.

PIP: The objective was to investigate the efficacy of 800 mcg misoprostol when administered to women pretreated with mifepristone for early pregnancy termination. In a randomized study, 150 women of 56 or fewer days' gestation were allocated to receive oral misoprostol either in a single dose of 800 mcg (Group A) or as two doses of 400 mcg administered sequentially 2 h apart (Group B); in each case misoprostol was administered 36-48 h after receiving mifepristone 200 mg orally. The overall success rate was 93%. 71 (95%) women who received a single dose of misoprostol and 69 (92%) who received the sequential dose aborted completely. There were two ongoing pregnancies in the first group (2.5%) and three (4%) in the second. The overall ongoing pregnancy rate was 3%. Side effects during the treatment were predominately gastrointestinal symptoms. Vomiting occurred in 30 (40%) women in Group A, compared with 23 (31%) in Group B (P = 0.12), while diarrhea occurred in 25 (33%) and 16 (21%), respectively (P = 0.05). Among women who had had symptoms of diarrhea, those in Group A rated the severity of their symptoms as significantly greater than the women in Group B (P = 0.03). 79% of the women in Group A and 83% in Group B returned for review. The mean duration of bleeding was 9.1 and 10.8 days, respectively. The difference of 1.7 days between the two means was statistically significant. The mean hemoglobin level at entry to study was 127 g/dl and 129 g/dl, respectively, while at follow up the recorded means were 129 g/dl and 130 g/dl, respectively. No significant difference was found between the two groups. In Group A, the mean difference between the diastolic blood pressure at baseline, and at the fourth hour after administration of the prostaglandin was 4.7 mmHg, this mean was significantly different from zero (P = 0.025). The combination of mifepristone and oral misoprostol provides an alternative method to abortion of pregnancies of up to 8 weeks' gestation.