Serum Progesterone in the Pregnant Baboon (Papio papio)

Publisher Website
Google Scholar
Abstract
Progesterone in serum samples obtained from baboons during the menstrual cycle and at random times from 60 days gestation to 24 h postpartum (term = 184 days) was measured by radioimmunoassay. Mean (.+-. SE) concentrations increased significantly (P < 0.01) from 0.5 .+-. 0.2 ng/ml (n = 7) to 4.9 .+-. 0.8 ng/ml (n = 8) during the follicular and luteal phases of the menstrual cycle, respectively. Mean (.+-. SE) concentrations between 60 days of gestation and term were 12.0 .+-. 0.9 ng/ml (n = 84), a value greater (P < 0.02) than that for the luteal phase. During the period of gestation studied there was no significant change in progesterone levels. Progesterone decreased (1.2 .+-. 0.5 ng/ml, mean .+-. SE, n = 5) by 24 h postpartum, indicating its dependence on the products of conception. In mid and late gestation serum progesterone concentrations of baboons differ from those in chimpanzees and humans, where they are elevated manyfold over those in the luteal phase, and in macaques where levels approximate luteal phase values.