What is the chance of a woman having a child with Down syndrome at age 35?

At the age of 35, the risk of a woman having a child with Down syndrome is indeed approximately 1 in 270. This statistic reflects the increasing likelihood of chromosomal abnormalities, including Down syndrome, with maternal age.

Down syndrome mainly results from nondisjunction, an error that occurs during cell division, particularly in older eggs. As women age, the quality and viability of their eggs are affected, leading to a higher risk of such errors occurring. By age 35, it is widely recognized in obstetric literature that the risk reaches around this figure, making it a critical age for discussions pertaining to genetic screening and prenatal counseling.

Understanding this risk is essential for expectant parents and healthcare professionals, as it can influence decisions regarding screening and potential interventions during pregnancy. Factors that contribute to this statistical risk include genetic predispositions and other maternal health considerations, which can further impact the likelihood of having a child with Down syndrome.