Association of serum folate levels during pregnancy and prenatal depression

Abstract

Objective

To evaluate the association between serum folate levels during pregnancy and prenatal depression and the extent to which obesity may modify this relationship.

Methods

This secondary data analysis leveraged data from a previous study of pregnant Kaiser Permanente Northern California participants who completed a survey and provided a serum sample between 2011 and 2013. Serum folate was assessed using the Center for Disease Control’s Total Folate Serum/Whole Blood Microbiological Assay Method. A score of 15 or greater on the Center for Epidemiologic Studies Depression Scale was defined as prenatal depression. We used Poisson regression to estimate risk of prenatal depression given prenatal serum folate status (low/medium tertiles vs. high tertile) in the full sample and in subsamples of women with pre-pregnancy body mass index in the (a) normal range and (b) overweight/obese range.

Results

Of the sample, 13% had prenatal depression. Combined low/medium folate tertiles was associated with prenatal depression (adjusted relative risk [aRR] = 1.97, 95% confidence interval [CI]: 0.93–4.18), although results did not reach statistical significance. This relationship was stronger among women with overweight/obesity than women with normal weight (aRR: 2.61, 95% CI: 1.01–6.71 and aRR: 1.50, 95% CI: 0.34–6.66, respectively).

Conclusion

Results suggest an association between lower pregnancy folate levels and prenatal depression that may be stronger among women with overweight or obesity. Future studies need to clarify the temporal sequence of these associations.

Keywords:

• Perinatal depression
• serum folate
• obesity
• body mass index
• antenatal depression
• nutrition

Acknowledgments

The authors thank Harpreet Chima, B.S for conducting the serum folate and homocysteine analysis.

Author contributions

This manuscript was made possible by a collection of work from the coauthors. M.M.H. collected the data, L.A.A. conceptualized the manuscript with input from B.C., M.M.H., D.K.L., N.N., N.N. conducted the analysis with oversight from L.A.A. and C.P.Q., J.U.A. and H.C. conducted the serum assays, L.A.A. drafted the manuscript. All coauthors reviewed and commented on subsequent drafts of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by a career development award to Dr Avalos [K01MH103444] by the National Institute of Mental Health (NIMH) and [R01HD101483]. This study was also partially funded by the Health Resources and Services Administration (HRSA) of the US Department of Health and Human Services (HHS) under R40MC21515.