THE RELATIONSHIP OF GONADOTROPHIN EXCRETION TO OVULATION DURING THE MENSTRUAL CYCLE

Abstract

ABSTRACT Serial determinations of urinary gonadotrophins, oestrogens and pregnanediol have been performed in one cycle from each of seven normally menstruating women. In all cycles there was evidence of ovulation as judged by steroid excretion although the actual time at which this event occurred varied considerably between individuals. Assays of »total gonadotrophic activity« by the mouse uterus test were conducted in two subjects. In only one woman was a midcycle peak noted. Follicle-stimulating hormone (FSH) was measured in five cycles. In four, levels tended to be higher at midcycle than at any other time although a definite peak of excretion was noted in only two of these. In the fifth subject FSH excretion was relatively constant throughout the period of investigation. Luteinising hormone (LH) was estimated in four cycles. In two a definite peak of excretion occurred but in only one was this closely associated with ovulation. In the remaining two women the midcycle LH peak was less pronounced. No definite correlation could be demonstrated between the excretion of FSH, LH and »total gonadotrophic activity« on the one hand and urinary steroid output on the other.