This paper is a review of the medical risks of late childbearing based on national health statistics and the medical literature. The two main topics covered are maternal risks, such as maternal mortality, obstetrical complications, miscarriage, and infertility, and risks to the infant, such as infant mortality, prematurity, and chromosomal abnormalities. The implications of advanced paternal age are discussed. The review concludes that there is no single age at which the risks of pregnancy and childbirth suddenly escalate. Rather, the increments in risk are gradual. For women who are in good health and have access to prenatal and postpartum care, what risks there are can be substantially mitigated through close medical monitoring.