EXCRETION OF FOLLICLE-STIMULATING AND LUTEINIZING HORMONE DURING LACTATION

Abstract

ABSTRACT The excretion of follicle-stimulating and luteinizing hormone (FSH, LH) during lactation in women was studied by biological methods in individual and pooled samples of urine. During the first and second postpartum weeks, the FSH activity was low and the LH activity quite high, probably due to contamination with remaining chorionic gonadotrophin. Thereafter the FSH and LH values and the relationship between these hormones did not differ from those found during the normal menstrual cycle. Moreover, an increase in the LH excretion was observed in one nursing mother, though ovulation and menstrual bleeding did not follow. It was concluded, that anovulation and amenorrhoea during lactation might be due to ovarian refractoriness by an unknown mechanism, rather than to gonadotrophic dysfunction.