Study Reveals Link Between Maternal Vitamin D During 1st Trimester and Pregnancy Outcomes - Video

Low vitamin D levels in the first trimester of pregnancy are associated with higher rates of preterm birth and decreased fetal length, according to a new study led by researchers in the Penn State Department of Nutritional Sciences. This research provides evidence that early pregnancy or even preconception may represent critical time points for intervening with women who have low vitamin D status, to optimize pregnancy outcomes. The findings are published in The American Journal of Clinical Nutrition.

The researchers tested blood samples from 351 women recruited pregnant women across the United States between 2010 and 2013.

Vitamin D was measured in terms of nanomoles per liter (nmol/L) of blood. When the researchers compared outcomes for women with vitamin D insufficiency (less than 50 nmol/L) to women with sufficient vitamin D (more than or equal to 50 nmol/L), they found no statistical differences in pregnancy outcomes. However, when the researchers compared pregnancy outcomes across a wider range of vitamin D concentrations, they found that pregnant women with first trimester vitamin D concentrations lower than 40 nanomoles per liter were four times more likely to experience a preterm birth compared to women with vitamin D concentrations more than or equal to 80 nanomoles per liter.

Women with higher levels of vitamin D experienced a small but statistically significant increase in fetal length.

When the researchers examined maternal vitamin D levels during the second trimester of pregnancy, they saw no difference in fetal growth patterns or pregnancy outcomes in women with lower versus higher vitamin D status. They said more women in the study had healthy levels of vitamin D during the second trimester, so that may have diminished their abilities to detect results. Still, they said this result required more research to fully understand.

Results pointed to the potential value of taking a supplement containing vitamin D for women who are planning a pregnancy, the researchers said.

Reference: https://www.psu.edu/news/health-and-human-development/story/vitamin-d-matters-during-first-trimester-researchers-find