Current studies in contraception: the use of a long-acting progestogen by injection. (Presented at the Forty-sixth South African Medical Congress Durban July 1967)

148 women (age 15-40 years) of known fertility attending the Headquarters Center of the Family Planning Clinics of Los Angeles from 1964 were injected with medroxyprogesterone acetate (150 mg) at 90 day intervals for a total of 1285 woman-months use. Bleeding patterns were irregular with some excessive and prolonged bleeding. By the third injection period bleeding duration was close to that of untreated women. 25.2% discontinued 5.8% due to excessive bleeding. There were no pregnancies. In ovulation studies performed on 30 women volunteering to stop therapy 1/3 were restored within 6 months (range 4.5-13 months). Consistent ovulation returned much later in some more than 18 months.