The effect of parity and gravidity on the outcome of medical termination of pregnancy

Background: Previous pregnancies may influence the success of medical termination of pregnancy. Objectives: To determine the effect of parity and gravidity on the successful termination of pregnancy using mifepristone and misoprostol. Methods: The medical files of all patients attending a department of obstetrics and gynecology during the years 2006 and 2007 for the purpose of medical termination of pregnancy at ≤ 49 days of gestation were analyzed retrospectively. The medical history, previous pregnancies and deliveries were recorded. Mifepristone was administered orally followed by 400 mg of misoprostol 48 hours later. A second dose of misoprostol was offered 2 weeks later if uterine content thickness was more than 15 mm. Then, after 24 hours, if uterine content thickness was more than 15 mm the uterus was evacuated by dilation and curettage. Results: Of 403 women, 349 (86.6%) aborted following the basic regime; 207 (51.4%) (group A) were primiparous while 196 (48.6%) (group B) had at least one prior pregnancy. Uterine curettage was performed in 17 patients (8.2%) in group A and in 37 (18.9%) in group B (P = 0.002). When patients with a history of a previous abortion were excluded from group B, 32 of 143 (22.4%) required curettage (P < 0.001). When patients without a history of previous cesarean section were excluded, 10 of 52 (19.2%) underwent curettage (P = 0.038). Conclusions: Previous pregnancies negatively affect the success of medical termination of pregnancy, especially in women with a previous term pregnancy. This information is important when counseling women about the method of pregnancy termination.