Alternative treatments in oral postcoital contraception: interim results

The study compares the effectiveness and acceptability of three regimes of postcoital contraception: 1) ethinylestradiol 100 micrograms/levonorgestrel 500 micrograms repeated after 12 hours (Yuzpe method); 2) danazol 600 mg repeated after 12 hours; and 3) RU486 600 mg single dose. Between 1 April 1990 and 15 October 1990, 215 women were selected and randomly allocated to the three treatment groups. One hundred and sixty eight were fully followed up, 35 ongoing and 8 lost to follow-up. All women had regular cycles and were aged 16-45 years. All treatments were given within 72 hours of unprotected intercourse and follow-up was until normal menstruation or diagnosis of pregnancy. beta-HCG was measured quantitatively where there was a suspicion of pregnancy. The data obtained show similar failure rates (Yuzpe 1/57, danazol 2/57, RU486 1/54) but more side-effects in the Yuzpe group (nausea 74.1%, vomiting 22.4%, breast tenderness 22.4%) than in the other two (danazol: nausea 31.6%, vomiting 3.5%, breast tenderness 19.3%) and (RU486: nausea 36.4%, vomiting 3.6%, breast tenderness 23.6%). There was one apparent allergic reaction in the danazol group. RU486 caused greater cycle disturbance, prolonging the cycle considerably. Initial results suggest that danazol and RU486 may be much more acceptable methods of postcoital contraception due to reduced side-effects and, in the latter case, single dose. Although numbers are small at present, the effectiveness of the newer methods appear similar to Yuzpe.