Note – Nondisjunction – Advanced Maternal Age – Down Syndrome

At least 50% of all cases instances of Down syndrome (plus other sorts of trisomies such as XXX, XXY) are conceived by women over 35 years of age. The number of total deliveries by such women represent a very small proportion of all births (although growing)*. Would aging women abstain from pregnancies, the burden imposed on innocent embryos would decrease by at least 50%.

* See a report under “News” on “Geriatric Mothers”