Black women are more likely to deliver premature babies when a vitamin D deficiency is found during pregnancy, a new study, led by the University of Pittsburgh Graduate School of Public Health, has found.
According to the research, which included Puerto Rican women, premature birth in nonwhite mothers naturally going into labor before the pregnancy is considered full-term, at 37 weeks, decreased by up to 30 percent as vitamin D levels were increased in the blood, News Medical reports.
“Vitamin D is unique in that while we get it from our diets, our primary source is our body making it from sunlight,” said lead author Lisa Bodnar, associate professor in Pitt Public Health’s department of epidemiology, according to News Medical. “Previous studies using conservative definitions for vitamin D deficiency have found that nearly half of black women and about 5 percent of white women in the United States have vitamin D concentrations that are too low.”
The team did not find similar results for preterm birth in white women.
“We were concerned that finding this association only in nonwhite women meant that other factors we did not measure accounted for the link between low vitamin D levels and spontaneous preterm birth in black and Puerto Rican mothers,” Bodnar stold News Medical. Bodnar and her colleagues took into consideration variables such as socioeconomics, fish intake and physical activity, but “even after applying these methods, vitamin D deficiency remained associated with spontaneous preterm birth,” she said.
Premature babies who don’t make it to at least 37 weeks often die. Those that survive often have developmental complications ranging from chronic lung disease to deafness to learning and cognitive disabilities, another author of the study, Hyagriv Simhan, chief of the division of maternal-fetal medicine and medical director of obstetrical services at Magee-Women’s Hospital of UPMC, told News Medical.
The study used samples from more than 700 premature births and 2,600 full-term births at 12 medical centers in the U.S. from 1959 to 1965.
“It is critical to repeat this study in a modern sample,” said Bodnar, acknowledging that pregnant women in the 21st century smoke less, receive more vitamin D in their foods but receive less sun exposure than women back then. “Further, it is especially important to understand how vitamin D influences preterm birth among black mothers. Vitamin D supplementation could be an easy way to reduce the high rates of preterm birth in this group.”
The study was founded by the National Institutes of Health.