Abstract

EFFECT OF HORMONES ON THE PHYSIOLOGICAL AND BEHAVIOR PROCESSES THAT INFLUENCES FERTILITY

Abdul Wahid Shah

Abstract

This chapter reviews the complex and diverse roles that hormones play in mediating the physiological and behavioral processes that influence human fertility. Much of the focus is on hormones of the reproductive axis, which mediate the physiological processes governing fertility and provide powerful modulation of sexual behavior. Secretion of these hormones changes over the life span. Reproductive hormones are secreted in surprisingly high levels in prenatal development and at this time help set the stage for later development of normal reproductive physiology and behavior in adulthood. There is then a period of childhood quiescence, when the reproductive axis is essentially ―turned off‖, followed by a cascade of hormonal changes that occur with puberty. In males, reproductive hormone secretion is rather stable in the adult years, with a slow decline in levels occurring with aging. In contrast, much greater fluxes in hormone secretion occur throughout adulthood in women, with large changes in hormone secretion occurring over the course of each menstrual cycle, followed by a period of irregular hormone secretion during the transition to menopause and ultimately a marked decline in reproductive hormone levels in the postmenopausal period.

Keywords: lead, nervous system, N-acetylcystein, biomarkers.