INCREASED PARITY AND RISK OF TRISOMY-21 - REVIEW OF 37110 LIVE BIRTHS

Routine amniocentesis for all women over the age of 35 for detecting t risomy 21 has been the world standard for nearly two decades. It is ba sed on a calculated tradeoff: the documented increased risk of trisomy 21 with advancing age versus the risk of fetal loss secondary to the amniocentesis procedure. Recent data suggest that more specific indivi dual estimates of risk can be made with a combination of maternal age and serum markers.(1) We have reported a trend towards an increased ri sk of trisomy 21 with increased parity.(2) Given the uniqueness of our population-ultra-Orthodox Jewish mothers who have a high rate of deli very over the age of 35, high parity, and who abstain from prenatal sc reening and abortion-we had an opportunity to study the interrelation of age and parity.