[Action of estroprogestatives on the endometrium. Histochemical study]. / Action des oestroprogestatifs sur l'endomètrie. Etude histochimique.

PIP: RNA content was analyzed in endometrial biopsies from 55 women taking 9 different oral contraceptives by a semiquantitative histochemical fluorescence technique. The data were grouped arbitrarily into group 1, endometria from women taking pills containing .05 mg ethinyl estradiol and either 1-4 mg norethisterone, 2 mg norgestrienone, 4 mg megestrol, or .5 mg norgenestrol; and group 2, higher estrogen doses and either 2.5 or 5 mg lynestrenol, 2 mg ethynodiol diacetate, or 5 mg norethisterone. There were 34% normal endometria in Group 1 and 15% in group 2; 48% undifferentiated in Group 1 and 40% in Group 2; 17% atrophic endometria in Group 1 and 45% in Group 2. These endometrial classes were unrelated to duration of pill use. RNA was present in undifferentiated mucosa in variable amounts inversely proportional to the degree of differentiation. RNA was absent in atrophic endometria, and usually depleted in Pill Group 2 except for biopsies from ethynodiol diacetate users. It is concluded that RNA was present in undifferentiated endometrium so that these target tissues would be ready to respond to steroid hormones.^ieng