Recent evidence suggests that fecundity in women begins to decline 15 or more years before the average age of menopause, but the physiological mechanisms of this process are poorly understood. Ovarian function is an important proximate determinant of fecundity, and can be assessed through salivary measurement of circulating ovarian steroids. The research proposed will examine the relationship between age and ovarian function by determining, for three groups of regularly-cycling women, ages 35-39, 40-44, and 45-49, (1) episodic patterns of luteal progesterone release in saliva and (2) patterns and levels of salivary estradiol across the menstrual cycle. Comparisons will be made across groups and with previously-determined profiles of younger women (under 35 years of age). This study will seek to identify specific aspects of ovarian function which may be altered in women of late-reproductive age, and thus which may contribute to impairment of fecundity. The results of this research will contribute to understanding of this process in our own population. They will also help to provide additional bases for study of the age structure of fecundity in other populations of anthropological interest, and for consideration of the historical development of human menopause.
