Omega-3 Fatty acids and gestational length in a high-risk psychiatric population due to psychiatric morbidity and medication exposure during pregnancy.

Objective: Premature birth is associated with infant morbidity and mortality. Women with psychiatric disorders represent an at-risk population for premature delivery and other obstetrical complications. The primary aim of this study was to assess the association between omega-3 fatty acid use and length of gestation.

Methods: Data from the National Pregnancy Registry for Atypical Antipsychotics were used. This prospective study included pregnant women exposed and unexposed to atypical antipsychotics during pregnancy. The outcomes of gestational length, birth weight, and preeclampsia were examined in relation to omega-3 use during pregnancy. Omega-3 use was operationalized from a first-trimester interview as a dichotomous variable.

Results: Of 361 women who were examined for eligibility, 233 women had a singleton birth as well as a valid response on the omega-3 item and information on at least one of the outcome measures. Ninety-seven (41.6%) women used omega-3 during pregnancy. Omega-3 users were older, more educated, and more likely to be married than nonusers. The users were less likely to have smoked during their first trimester and were marginally less likely to use antidepressant medications anytime during pregnancy. There were no significant differences in primary diagnoses or atypical antipsychotic, alcohol, or prenatal vitamin use. In an unadjusted model, there was a significant increase of between 4 and 5 days (0.65 weeks; 0.00-1.25) in gestational length among the omega-3 users. This result was no longer significant after adjusting for confounding variables, with an increase of approximately 4 days (0.53 weeks; -0.11 to 1.16). Omega-3 use was not significantly associated with a difference in birth weight or preeclampsia.

Conclusions: We found a trend for a modestly increased length of gestation among the omega-3 fatty acid users, although these were not significant after controlling for the exposures of smoking and antidepressant use. We did not find a decreased risk for preeclampsia among the users of omega-3 fatty acids or increased birth weight. In consideration of the risk factors for obstetrical and neonatal complications as well as implications for infant and child development, it would be clinically important to understand the variables that may additively decrease obstetrical risks in this population.