A study by the Penn State Department of Nutritional Sciences found that low vitamin D levels in the first trimester of pregnancy are associated with higher rates of preterm birth and decreased fetal length.
“More than 25% of women who are pregnant or lactating have lower than recommended levels of vitamin D,” said Alison Gernand, one of the study's authors.
Women with higher levels of vitamin D were found to have experienced small but statistically significant increases in fetal length.