Multinational comparative clinical evaluation of two long-acting injectable contraceptive steroids: Norethisterone oenanthate and medroxyprogesterone acetate: 2. Bleeding patterns and side effects

Abstract

The present paper reports the bleeding patterns and side effects experienced by women using norethisterone oenanthate (NET-OEN) and depot-medroxyprogesterone acetate (DMPA) in a WHO-sponsored comparative trial. Only a small minority of women had consistently normal cycles: the vast majority experienced some menstrual abnormality, with 47% of NET-OEN and 70.6% of DMPA users not having any normal cycles. Amenorrhoea was significantly more frequent with DMPA than with NET-OEN and its incidence increased with time. At the end of one year 35% of DMPA and 8.6% of NET-OEN users had total amenorrhoea. There were only minor differences between the two drugs with respect to the frequency or duration of bleeding episodes, but DMPA caused significantly more spotting than NET-OEN. With both treatments there were large individual variations and the bleeding pattern was totally unpredictable. Headache, the most important nonmenstrual side effect, was reported by 6.9% of the NET-OEN and 10.7% of the DMPA users. In the case of DMPA its incidence increased with time. Other complaints such as abdominal discomfort and nervousness were reported with similar frequency on both drugs. There was, with both treatments, a slight increase in body weight and a decrease in blood pressure.