INFLUENCE OF OOPHORECTOMY, LUTEECTOMY, FOETAL DEATH AND DEXAMETHASONE ON THE PERIPHERAL PLASMA LEVELS OF OESTROGENS AND PROGESTERONE IN THE PREGNANT MACACA MULATTA

Abstract

The influence of bilateral oophorectomy, luteectomy, dexamethasone injections and foetal death on the peripheral plasma levels of oestrogens¹⁾ and progesterone was studied in pregnant rhesus monkeys. After bilateral oophorectomy and luteectomy, pregnancy proceeded normally and the plasma levels of oestrogens and progesterone attained levels similar to those in intact monkeys, but the progesterone levels after parturition were comparatively lower. Dexamethasone injections into pregnant monkeys had no deleterious effect on the outcome of gestation. Abrupt and dramatic decreases in total oestrogens, oestrone and oestradiol levels occurred during dexamethasone injections into intact and oophorectomized pregnant monkeys but no significant changes in progesterone levels in plasma were observed. Spontaneous intra-uterine foetal death was accompanied by decrease in oestrogens, but no changes in the plasma levels of progesterone. In experimentally induced foetal death, the oestrogen and progesterone levels in plasma decreased prior to abortion. These data demonstrate the relative influence of the ovaries, adrenals and the placenta on the maternal plasma levels of oestrogens and progesterone in the pregnant rhesus monkey.