Studies indicate that gastroschisis is associated with maternal age, ethnicity, and acculturation. This analysis was conducted to further define the associations between gastroschisis and parental Hispanic ethnicity and acculturation, and to determine whether such associations vary by maternal age. METHODS This study was based on data from mothers of 753 gastroschisis cases and 6,496 control infants in the National Birth Defects Prevention Study. The relationships between gastroschisis and both parental Hispanic ethnicity and acculturation, within maternal age strata (<20 versus ≥20 years at conception), were assessed using logistic regression and principal component analyses. RESULTS The risk of gastroschisis in offspring of women <20 years old was not significantly associated with parental Hispanic ethnicity or acculturation. Among mothers ≥20 years old, US-born non-Hispanic white parents had a lower risk of gastroschisis in offspring as compared to either US-born Hispanic (odds ratios [ORs] ranging from 0.55 to 0.60) or English-speaking Hispanic (ORs ranging from 0.58 to 0.65) parents. Further, compared with US born Hispanic women ≥20 years, the risk of gastroschisis was lower for Hispanic women who had lived in the US <5 years (OR=0.35, 95% confidence interval [CI]: 0.17, 0.74) or who migrated to the US at ≥20 years (OR=0.47, 95% CI: 0.25, 0.88). CONCLUSIONS These results provide further evidence that gastroschisis risk is associated with ethnicity and some aspects of acculturation. Additionally, these associations were limited to the offspring of women who are ≥20 at the time of conception.