Genetic Counseling for the Older Pregnant Woman: New Data and Questions

Abstract

It has become accepted medical practice to inform pregnant women 35 years of age and older of their increased risk of having a child with chromosome abnormality in comparison to younger women, and to offer prenatal diagnosis to determine whether the fetus is affected. The focus has been on the older pregnant woman because the autosomal trisomies 21 (the Down syndrome), 18 and 13 have been found to be more common in the children of older mothers and because most of the affected infants have been born to women over 35.1 It has therefore been postulated that the extra chromosome . . .