Clinical investigation of the biological effects of a new combination low-dose oral contraceptive ('Ovostat E').

SummaryEleven healthy fertile women volunteers, aged 20 to 30 years, participated in a long-term investigation over 12 cycles into the effects of a low-dose contraceptive containing 1 mg lynestrenol and 0.050 mg ethinyl oestradiol per tablet. Urinary LH, pregnanediol and oestrogen, and serum progesterone and oestradiol values were estimated, and vaginal smears and endometrial biopsies taken, according to a fixed schedule, on the third, sixth, seventh and twelfth treatment cycles. SGOT and SGPT values were also determined. On the basis of the hormonal determinations, it was established that ovulation was inhibited in all the cycles studied. Examination of the endometrial biopsies showed a drug effect in all cases and there was no secretory activity in any of the samples. Hypoplasia was found in 6 out of a total of 22 samples. The karyopyknotic index curve in the vaginal cytology was clearly biphasic and resembled the normal cyclic curve. The indices showed a clear decrease during the sixth treatment cycle,...