A COMPARATIVE-STUDY OF 2 LOW-DOSE COMBINED ORAL-CONTRACEPTIVES - RESULTS FROM A MULTICENTER TRIAL

A comparative multicenter clinical trial of two low-dose combined oral contraceptives (OCs) was conducted in Malaysia, Egypt, Thailand, and Mexico. Efficacy, safety and acceptability were investigated in women taking either a norgestrel-based (NG) OC or a norethindrone acetate-ba sed (NA) OC. This paper includes analysis of 892 women, all of whom we re at least 42 days but within 26 weeks postpartum and randomly alloca ted to one of the above OCs. Follow-up visits were scheduled at 1, 4, 8 and 12 months after admission. Baseline sociodemographic characteris tics were similar for both groups, as well as compliance. There were n ine unintended pregnancies reported; eight of these occurring in the N A group. Adverse experiences were minor with headaches and dizziness b eing the most common complaints; frequency of reports was similar in b oth groups. The group taking the NG-based OC had significantly (p<.05) fewer menstrual-related complaints. Discontinuations due to menstrual problems were significantly more common among NA users (primarily ame norrhea). Discontinuations in the NG group were primarily for other pe rsonal reasons, e.g. unable to return to the clinic. There was also a significant difference between the two groups for the 11-month gross c umulative life table discontinuation rates due to menstrual problems ( p<.01); the NA group had the higher rate.