The Aging of Gametes, Heteroploidy, and Embryonic Death

Abstract

ABSTRACT Experimental evidence obtained from amphibians as well as from mammals reveals what role the aging process of gametes plays in the pathogenesis of reproductive wastage in virtually all animals. The data indicate that senescence may affect gametes of both sexes and that it may occur both before and after ovulation and ejaculation respectively. A wide range of reproductive abnormalities may be caused by time‐related phenomena including fetal developmental and chromosome defects, twinning, abortion and possibly others. The pathological mechanism of these anomalies, as reflected in the experimental findings, is discussed in some detail.