Serum prolactin profiles of normal human conceptual cycles

Commencing on day 10 of the menstrual cycle through onset of subsequent menses, or confirmation of pregnancy, daily sera collected from 15 women planning pregnancy were analyzed by radioimmunoassays (RIA) for prolactin (hPRL), estradiol-17 beta and luteinizing hormone (hLH). Two of the observed subjects became pregnant in the single cycles studied. The profiles of these hormones during the early gestation following spontaneous ovulation were established. No distinct midcycle peaks of hPRL were observed in either subject. Enormous spikes were observed in daily prolactin values, with wide variations between subjects.