Maternal Vitamin D Status and Small-for-Gestational-Age... : Obstetrics & Gynecology (original) (raw)

Contents: Original Research

Maternal Vitamin D Status and Small-for-Gestational-Age Offspring in Women at High Risk for Preeclampsia

Gernand, Alison D. PhD, MPH, RD; Simhan, Hyagriv N. MD, MS; Caritis, Steve MD; Bodnar, Lisa M. PhD, MPH, RD

Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, the Division of Maternal-Fetal Medicine, Magee-Women’s Hospital, and the Departments of Obstetrics, Gynecology and Reproductive Sciences and Pediatrics, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.

Corresponding author: Lisa M. Bodnar, PhD, MPH, RD, University of Pittsburgh Graduate School of Public Health, A742 Crabtree Hall, 130 DeSoto Street, Pittsburgh, PA 15261; e-mail: [email protected].

Supported by the National Institutes of Health grant HD056999 (Principal Investigator: Dr Bodnar).

The authors thank Mark Klebanoff for his assistance with analysis methods and Jill Diesel and Katharyn Baca for their assistance with data preparation.

Presented as a scientific poster at the Experimental Biology Meeting, April 20–24, 2013, Boston, Massachusetts.

Financial Disclosure The authors did not report any potential conflicts of interest.

OBJECTIVE:

To examine the association between second-trimester maternal serum 25-hydroxyvitamin D concentrations and risk of small for gestational age (SGA) in singleton live births.

METHODS:

We assayed serum samples at 12–26 weeks of gestation for 25-hydroxyvitamin D in a sample of participants in a multicenter clinical trial of low-dose aspirin for the prevention of preeclampsia in high-risk women (n=792). Multivariable log-binomial regression models were used to assess the association between 25-hydroxyvitamin D and risk of SGA (birth weight less than the 10th percentile for gestational age) after adjustment for confounders including maternal prepregnancy obesity, race, treatment allocation, and risk group.

RESULTS:

Thirteen percent of neonates were SGA at birth. Mean (standard deviation) 25-hydroxyvitamin D concentrations were lower in women who delivered SGA (57.9 [29.9] nmol/L) compared with non-SGA neonates (64.8 [29.3] nmol/L, _P_=.028). In adjusted models, 25-hydroxyvitamin D concentrations of 50–74 nmol/L and 75 nmol/L or greater compared with less than 30 nmol/L were associated with 43% (95% confidence interval [CI] 0.33–0.99) and 54% (95% CI 0.24–0.87) reductions in risk of SGA, respectively. Race and maternal obesity each modified this association. White women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 68% reduction in SGA risk (adjusted risk ratio 0.32, 95% CI 0.17–0.63) and nonobese women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 50% reduction in SGA risk (adjusted risk ratio 0.50, 95% CI 0.31–0.82). There was no association between 25-hydroxyvitamin D and risk of SGA in black or obese mothers.

CONCLUSION: