Maternal Vitamin D Status and Cesearean Birth: Is There a Connection?

Background: While conducting a larger study on vitamin D status in newly delivered mothers and their infants, we obtained information on vitamin D status in women with cesarean births. Historically, when access to cesarean birth was limited, rickets was responsible for high rates of maternal death in childbirth. Methods: The study took place in an urban Boston hospital between 2004 and 2006. Blood was drawn pospartum in the hospital. Vitamin D status was measured by 25(OH)D levels: levels <15 ng/ml (<37.4 nmol/L) were considered severely deficient. Results: We obtained blood from 206 women of whom 162 (79%) had vaginal births and 44 (21%) had cesareans. Seven women were excluded due to missing data. Of women delivering vaginally, 16% (25/156) were severely vitamin D deficient; of women having a cesarean, 33% (14/43) were severely deficient. In multivariate logistic regression, controlling for skin color, race, season of birth, use of prenatal vitamins, and time spent outside (exposure to sunlight), women who had a cesarean birth were 2.6 times more likely to have severe vitamin D deficiency than women who had a vaginal delivery (AOR 2.57; 95% CI 1.01-6.57). Conclusion: Severe vitamin D deficiency in our sample was associated with increased likelihood of cesarean birth.