Vitamin D in Early Pregnancy Could Boost Baby's Health

vitamins vitamin D

Key Takeaways

  • More than a quarter of pregnant women are insufficient in vitamin D

  • New research suggests that adequate levels of the nutrient are especially important in the first trimester

  • Babies born to women with low levels of vitamin D in early pregnancy were more likely to be born prematurely

THURSDAY, Feb 6, 2024 (HealthDay News) -- Getting enough vitamin D, the "sunshine vitamin," during early pregnancy could be important for infant health, new research suggests.

Researchers at Penn State found that infants born to women deficient in the nutrient were more likely to be delivered prematurely.聽

Those newborns were also more likely to be smaller compared to babies delivered by women who'd gotten enough of the vitamin in their first trimester.

69传媒淭his study provides evidence that early pregnancy -- and even pre-conception -- nutrition is vitally important,69传媒 lead study author said. She was a doctoral student at Penn State's University Park campus when the study was conducted, and is now an associate research scientist at Heluna Health.聽

69传媒淲e can't just assume that everybody is deficient, but proper nutrition is something that needs to be on your radar if you may become pregnant," senior study author , associate professor of nutritional sciences at Penn State, added.聽

69传媒淭his study provides evidence that vitamin D appears to be an important part of a pregnant woman69传媒檚 nutritional health," Gernand said.

The research appears in the February issue of .

Vitamin D is considered essential to health, and the body generates it naturally via the absorption of sunlight by the skin. However, many people no longer get enough vitamin D in their daily lives.

In fact, prior research has found that 69传媒渕ore than 25% of women who are pregnant or lactating have lower than recommended levels of vitamin D,69传媒澛爊oted Gernand.聽

69传媒淎 lot of the development early in pregnancy requires vitamin D, so we conducted this study to better understand how early-pregnancy vitamin D status is related to pregnancy outcomes," she explained in a Penn State news release.

Vitamin D insufficiency is defined as blood levels of the nutrient that are below 50 nanomoles per liter (nmol/L) of blood.聽

In the new study, the researchers looked at first trimester vitamin D levels of 351 pregnant U.S. women who'd enrolled in a major federal study between 2010 and 2013. 聽

At first, there appeared to be no differences in pregnancy outcomes for women who were either above or below the 50 nmol/L blood level for vitamin D.

But concerning differences did arise when researchers looked at a wider range of vitamin D concentrations.

As Gerland and Beck reported, women with blood levels lower than 40 nmol/L during their first trimester had rates of preterm birth that were four times that of women who had vitamin D levels of 80 nmol/L or above.聽

What's more, there was a trend to smaller babies (based on fetal length) among women as vitamin D levels during the first trimester decreased.

The researchers stressed that these results are preliminary: There were few premature births in the study group overall, so a larger study may be needed to confirm the findings.

Vitamin D levels during the second trimester appeared to have no relation to pregnancy outcomes.聽

That could be because vitamin D levels tended to improve among the women later in pregnancy, although more study is needed to understand the finding, the researchers said.

The take-home message from the study: Women may need to boost their vitamin D levels early in pregnancy.

69传媒淚ndividual women may or may not need supplements depending on their diet and lifestyle," Gerland said. "But healthy nutrition is critical for promoting the healthy development of a fetus. This research indicates that vitamin D levels -- along with iron, folate and other essential nutrients in pregnancy -- should be monitored and understood by obstetricians and women early on to promote healthy birth outcomes.69传媒

The study was funded by the U.S. National Institutes of Health, the University of Utah and the Penn State Department of Nutritional Sciences.聽

More information

Find out more about the nutrients you need during pregnancy at

SOURCE: Penn State, University Park, news release, Feb. 3, 2025

What This Means For You

Research suggests that adequate vitamin D in early pregnancy is vital to good obstetric outcomes.

Originally published on , part of the .