Levels of immunoreactive inhibin-like material in urine during the menstrual cycle

Abstract
Using a specific and sensitive radioimmunoassay, inhibin-like material was determined in the urine of 8 healthy women with normal menstrual cycle length of 28 .+-. 4 days. A cyclic variation in urinary immunoreactive inhibin levels during the menstrual cycles was observed with a sharp rise in levels 3-4 days prior to luteinizing hormone (LH) and FSH peaks. These levels of immunoreactive inhibin may thus serve as a parameter to detect impending LH surge.