Clinical experience with a triphasic oral contraceptive ('Trinordiol') in young women.Curr Med Res Opin. 1983; 8(6):395-404.CM
Seven hundred and fifty cycles of treatment with a new triphasic oral contraceptive (WL-49(50). 'Trinordiol') containing the lowest quantity of steroids of all available preparations were evaluated in 75 healthy young women (mean age 19.6 years), 70% of whom had regular, normal cycles. Sixty-five percent had not used contraception before; the others had previously been on combined or progestagen-only oral contraceptives or had an IUD. The mean length of treatment with the triphasic preparation was 10 cycles. No pregnancy was recorded during the 750 cycles of treatment. Fifteen (20%) women dropped out of the study for medical reasons, essentially breast tenderness, weight increase, spotting and nausea, in decreasing order of frequency. Mastalgia was present in 21% of the women (8.9% of the cycles) during triphasic oral contraception, but this symptom disappeared in more than half of the cases within 3 months of continued use. Other side-effects were less frequent: vaginal discharge (4.4% of the cycles), nausea (3.7%), abdominal and leg cramps (2.8%), headaches (3.2%) and weight increase (3%). Spotting and breakthrough bleeding were reported during only 1.9% of the cycles, a remarkably low frequency. No absence of withdrawal bleeding was noted. Weight and blood pressure changes were minimal and never reached statistical significance. Hypertension developed during triphasic medication in 1 predisposed individual. Complaints of oestrogen-related symptoms such as breast tenderness and digestive disorders were probably due to the reduced progestagen content of the preparation compared with combined low fixed daily dose oral contraceptives. However, no increases in dysmenorrhoea and/or premenstrual tension were noted. It is concluded that the triphasic preparation provides effective contraception with excellent cycle control and minimal side-effects, which should help to increase the acceptability of low-dose combined oral contraceptives.