Maternal education modifies the age‐related increase in the birth prevalence of Down syndrome

OBJECTIVE: To test the hypothesis that the age-related increase in the birth prevalence of Down syndrome is less for women with higher levels of education due to their more frequent use of prenatal diagnosis. METHODS: We compared the effects of maternal age on the odds of Down syndrome at birth, and on amniocentesis use, in women with <12 years of education with those who had >or=12 years of education. We used a national data set and analyzed the effects of education separately for African Americans (N = 1643054), and non-Hispanic whites (N = 6676885) in the US birth cohorts of 1989-1991. Analyses included Mantel-Haenszel and logistic regression models with the likelihood ratio test to assess interactions between education and age effects. RESULTS: For both African Americans and non-Hispanic whites, the age-related increase in the odds of Down syndrome was substantially less for women with higher levels of education (p < 0.001). For both ethnic groups, women with higher levels of education were more likely to use amniocentesis (p < 0.001). CONCLUSIONS: Our results suggest that women with higher levels of education are more likely to use prenatal diagnosis. Moreover, this effect of education on prenatal diagnosis use, translates into a lower rate of age-related increase in the birth prevalence of Down syndrome.