Ensuring adequate vitamin D, the “sunshine vitamin” levels during early pregnancy could be important for infant health, according to new research from Penn State. The study found that vitamin D deficiency in early pregnancy is linked to a higher risk of premature delivery and smaller newborn size.
“This study provides evidence that early pregnancy and even pre-conception nutrition is vitally important,” said lead study author Celeste Beck. Senior study author Alison Gernand added that while not everyone is deficient, maintaining proper nutrition should be a priority for those planning pregnancy.
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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.
Published in the American Journal of Clinical Nutrition, the study analyzed first-trimester vitamin D levels in 351 pregnant U.S. women. Researchers observed a significant correlation between low vitamin D levels and adverse pregnancy outcomes:
- Women with vitamin D levels below 40 nmol/L had four times the risk of preterm birth compared to those with levels of 80 nmol/L or higher.
- Lower vitamin D levels were associated with smaller fetal size.
Interestingly, vitamin D levels during the second trimester showed no clear link to pregnancy outcomes, possibly due to natural improvements in vitamin D levels as pregnancy progressed.
Although the findings suggest a strong connection between vitamin D and pregnancy outcomes, researchers noted the need for more studies to confirm these results.
Practical Takeaways from the study
Women planning pregnancy should consider their vitamin D intake alongside other essential nutrients like iron and folate. While some may not require supplements, proper diet and lifestyle choices are crucial for fetal health. Obstetricians should monitor and address nutritional deficiencies early in pregnancy to support healthy birth outcomes.