Public health aspects of Down's syndrome (Mongolism)

Down's syndrome (trisomy 21) which is associated with childbearing in older women has declined in incidence as childbearing in older women has declined. Expectation of life has increased markedly over the same period, leading in turn to a rise in prevalence at older ages. Prenatal diagnosis now makes it technically possible to screen at risk pregnancies. Public health needs to consider the implications of the demographic and obstetric changes.