Female reproductive aging--ovarian and uterine factors

To review published data on ovarian and uterine aging in the human female.

Literature review.

Studies examining the effect of age on oocyte quality and uterine receptivity.

There is clear evidence in women having in vitro fertilization (IVF) and in normal oocyte donors that oocyte quality declines with age. Three studies of oocyte donation, one study of IVF, and multiple studies in subhuman mammalian species have all shown reduced implantation with aging, and endometrial biopsies in women over age 35 having IVF have shown a high incidence of delayed or absent secretory maturation. In one study of oocyte donation, the reduced rate of pregnancy in women over age 40 was corrected by doubling the dose of progesterone (P) administered to prepare the endometrium for implantation.

Conflicting opinions regarding the effect of aging on uterine receptivity in recipients of donated oocytes appear to have been because of use of high doses of P replacement. When doses more closely approximating physiological levels have been used, a decline of implantation with increasing age has been clearly demonstrated. Oocyte donation, through the use of oocytes from young normal women and an increased level of P replacement to aging recipients, corrects both of these defects.