NORETHINDRONE AND MESTRANOL. EXPERIENCE IN PRIVATE PRACTICE WITH A NEW LOW-DOSAGE ORAL CONTRACEPTIVE.

Until fairly recently the authors prescribed Enovid which contains 5 mg of norethynodrel plus .075 mg of ethinyl estradiol 3-methyl ether for their patients. It was found to be a completely effective contraceptive but the authors became concerned by the rather high incidence of gastrointestinal intolerance to this agent and by the occasional instances of recurrent menorrhagia or quite severe breakthrough bleeding. It was decided to give clinical trial to a tablet containing only 2 mg of norethindrone plus .1 mg of mestranol. A group of 79 married women of normal fertility was treated with this medication for periods ranging from 1 to 18 months. No pregnancy occurred during this observational period of 593 treatment cycles. Under the prescribed regimen all patients experienced menstrual-like bleeding at an interval of 26-28 days. In almost 50% of the treated patients the volume of flow was less than that previously experienced during normal menstruation. Dysmenorrhea was also frequently relieved. 1 patient experienced a heavy menstrual flow and passed a decidual cast. Her menstrual pattern then became normal as before. Breakthrough bleeding or spotting occurred in approximately one third of the patients but was rarely noted in more than 1 cycle. In the majority of instances this bleeding was minimal. No serious side reactions were observed and a number of patients previously proved intolerant of norethynodrel were able to take norethindrone without symptoms. Nausea occurred in 7 patients and it was at least in part responsible for discontinuance in 5. The method was found highly acceptable by virtually all patients and was overwhelmingly preferred to previously-used barrier techniques.