Low Doses of Progestogen as an Approach to Fertility Control

Abstract

A clinical program was undertaken to establish the contraceptive effectiveness of minimal hormonal supplementation with chloramadinone acetate .5 mg given daily in both a cyclic and continuous pattern. Nonlactating women of proven fertility 36 years and under were given the drug daily as a contraceptive. They were all involved in an intensive study of the reproductive system. With the cyclic use of .5 mg chlormadinone acetate there were 2 pregnancies on of which was due to failure of the patient to continue the regimen. The principal side effect was intramenstrual bleeding and spotting in about 20-25% studied. Endometrial biopsies showed that the drug did not prevent the development of a normal secretory endometrium this was seen in 80 of the 109 specimens. Of 122 urinary pregnanediol determinations done 33(27%) had concentrations at ovulatory levels. In culdoscopic findings follicular activity or corpora lute were found in 18 of 19 patients studied. Contraceptive protection was also afforded with continuous administration of the drug. With continuous administration of the drug approximately 60% of the women had cycles of 24-34 days the longer cycle being more common and 80-90% had 7 or less days of bleeding per month. The endometrium showed less evidence of normal secretory activity than that seen with cyclic administration of the same drug. Preliminary studies of ovarian biopsy specimens suggest that ovulation occurs as in cyclic treatment.