The role of prolactin in the restoration of ovarian function during the early post-partum period in the human female. I. A study during physiological lactation.

Serial plasma levels of prolactin, follicle-stimulating/ml hormone (FSH), luteinizing hormone (LH), 17beta-oestradiol (E) and progesterone (P) were determined by radio-immunoassay in ten healthy women during late pregnancy and puerperium until the occurrence of the first menstruation, at which moment an endometrial biopsy was taken. Prolactin concentrations, which were high during late pregnancy and the early post-partum period, declined thereafter but remained above 30 ng