Research Library
Maternal vitamin D deficiency increases the risk of preeclampsia.
Authors: Bodnar LM, Catov JM, Simhan HN, Holick MF, Powers RW, Roberts JM.
Source: J Clin Endocrinol Metab. 2007 May 29
Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania.; Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.; Magee-Womens Research Institute, Pittsburgh, Pennsylvania.; Vitamin D Laboratory, Section of Endocrinology, Nutrition and Diabetes, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts.
Context: Vitamin D has direct influence on molecular pathways proposed to be important in the pathogenesis of preeclampsia, yet the vitamin D-preeclampsia relation has not been studied. Objectives: We aimed to assess the effect of maternal 25-hydroxyvitamin D [25(OH)D] concentration on the risk of preeclampsia and to assess the vitamin D status of newborns of preeclamptic mothers. Design: Nested case-control study of pregnant women followed from <16 weeks gestation to delivery (1997-2001). Setting: Prenatal clinics and private practices. Patients: Nulliparous pregnant women with singleton pregnancies who developed preeclampsia (n=55) or did not develop preeclampsia (n=219). Women's banked sera was newly measured for 25(OH)D. Main Outcome Measure: Preeclampsia (new-onset gestational hypertension and proteinuria for the first time after 20 weeks gestation). Our hypotheses were formulated before data collection. Results: Adjusted serum 25(OH)D concentrations in early pregnancy were lower in women who subsequently developed preeclampsia compared with controls (geometric mean (95% CI): 45.4 (38.6, 53.4) nmol/l versus 53.1 (47.1, 59.9), p<0.01). There was a monotonic dose-response relation between serum 25(OH)D concentrations at <22 weeks and risk of preeclampsia. After confounder adjustment, a 50-nmol/l decline in 25(OH)D concentration doubled the risk of preeclampsia (adjusted OR (95% CI): 2.4 (1.1, 5.4)). Newborns of preeclamptic mothers were twice as likely as control newborns to have 25(OH)D <37.5 nmol/l (adjusted OR (95% CI): 2.2 (1.2, 4.1)). Conclusions: Maternal vitamin D deficiency may be an independent risk factor for preeclampsia. Vitamin D supplementation in early pregnancy should be explored for preventing preeclampsia and promoting neonatal well-being.