Anovular corpus luteum in a woman taking an oral contraceptive.

ABSTRACT

PIP When laparatomy was performed on 3 women treated with a combination-type oral contraceptive (5 mg lynestrenol, 150 MCG mestranol), an anovular corpus luteum was found in 1 ovary. Dating from the start of oral therapy, the times of the operations were Day 24, Cycle 1; Day 24, Cycle 2; and Day 23, Cycle 3 (anovular corpus luteum). The anovular corpus luteum was 6.5 mm long and 3.0 mm wide and had undergone considerable regression, about 3/4 of it having been converted into an avascular hyalinized mass. An unejected ovum, contour slightly altered and size approximately equal to that of ova in ovulation-ripe Graafian follicles, was situated in the center of the hyaline mass. The unejected ovum was the first one to be observed in a completely developed corpus luteum. The membrane pellucida was wider than usual, but the nucleus, nucleolus, and corona radiata cells surrounding the ovum had undergone little change. Hormone administration may have favorably influenced conditions of metabolism within the hyaline mass. Alterations in the anovular corpus luteum were compared with those found in the second treatment cycle in a corpus luteum formed during the first treatment cycle. The anovular corpus luteum was concluded to be the regressing corpus luteum of the first treatment cycle and approximately 65 days old.^ieng