The trend of delayed childbearing has implications for the increasing national burden of adverse perinatal outcomes across vulnerable racial-ethnic groups. The objective of this study was to investigate age-adjusted risk for adverse maternal-fetal outcomes among Asian Americans of advanced maternal age (≥35 years).
This was a retrospective cohort study using the 1992-2018 Natality data files. We calculated the prevalence of maternal-fetal outcomes: maternal diabetes, hypertensive disorders of pregnancy (HDP), C-section, small-for-gestational age (SGA), large-for-gestational age (LGA), and preterm birth. Adjusted binomial logistic regression was created to evaluate the association between maternal race/ethnicity and each of the maternal-fetal outcomes.
Compared with non-Hispanic Whites, Asian American women had reduced odds of diabetes, HDP, and LGA babies and increased odds of preterm birth, C-section delivery, and SGA, irrespective of the advanced maternal age group. The odds of developing specific adverse outcomes by advanced maternal age varied by Asian American ethnic subgrouping.
The risk of maternal-fetal outcomes varied among the ethnic subgroups of Asian Americans in the United States. Future studies should explore the sociocultural and environmental nuances that might explain these differences.

© 2021 Japan Society of Obstetrics and Gynecology.