Trisomy 21 and maternal age of menopause : does reproductive age rather than chronological age influence risk of nondisjunction ?

The biological basis underlying the increased risk of nondisjunction in offspring of women of advanced maternal age is not understood. We sought to test the hypothesis that maternal reproductive age (distance in time from approaching menopause) rather than chronological age is pivotal in the etiology of nondisjunction. Our results found no difference in age of menopause between women > or = 30 years old at delivery of a child with trisomy 21 (i.e., age-related nondisjunction) compared to controls. Among women < 30 years of age at delivery of a child with trisomy 21, none underwent premature menopause. Therefore, our findings fail to support the theory that reproductive age plays a major role in the etiology of nondisjunction.