New research published in the Journal of Clinical Endocrinology and Metabolism suggests that vitamin D supplementation during pregnancy may help improve Apgar scores in newborns.
There is much interest in vitamin D during pregnancy. Researchers are interested if low vitamin D levels during pregnancy increases risk of developing certain conditions during pregnancy, like preeclampsia, and certain complications, like needing a C-section. They’re also interested if low vitamin D levels during pregnancy increases risk of offspring developing a wide array of diseases, from cardiovascular diseases to autoimmune diseases to developmental disorders.
To date, we have lots of observational data showing that vitamin D deficiency is indeed linked to these diseases and complications. However, we’re still lacking good quantities of interventional data to see if vitamin D deficiency causes some of these diseases and complications.
In a new study, researchers from Dow University of Health Sciences in Karachi, Pakistan, conducted an interventional trial, to help shore up our lack of data in this realm.
The researchers enrolled 200 pregnant mothers into their study at the Civil Hospital in Karachi, Pakistan. The women were less than 20 weeks pregnant.
Half of the women were randomized to Group A, while the other half were randomized to Group B:
- Starting at 20 weeks and through pregnancy, Group A received daily ferrous sulfate (200 mg) and calcium (600 mg).
- Starting at 20 weeks and through pregnancy, Group B received daily ferrous sulfate (200 mg), calcium (600 mg) and vitamin D (4,000 IU).
The researchers wanted to know if there were differences in vitamin D levels, pregnancy outcomes and Apgar scores between the two groups. Apgar score is a scale that was developed in 1952 designed to assess the health of the newborn baby immediately after birth. Apgar is an acronym for appearance, pulse, grimace, activity and respiration, the five aspects the scale assesses. Apgar scores are typically given 1 and 5 minutes after birth.
The researchers tracked the women through pregnancy and delivery. After birth, what were the differences between mothers and babies in Group A vs Group B? Here’s what the researchers found:
- Sixty-nine percent of the babies born in Group B (the vitamin D group) had vitamin D levels over 30 ng/ml at birth, while only 18% of the babies born in Group A (no vitamin D) had vitamin D levels over 30 ng/ml.
- There was no difference in pregnancy outcomes between the two groups. Vitamin D supplementation in this trial had no impact on risk for preterm birth, gestational hypertension, preeclampsia, small for gestational age or delivery by C-section.
- However, babies of mothers in Group B (the vitamin D group) had significantly better 1 minute and 5 minute Apgar scores compared to group A (P=.03 for 1-minute, .05 for 5-minute).
The researchers had mixed feelings about their findings:
“While on one hand, our data demonstrate tolerability of vitamin D in daily dose of 4,000 IU starting at 20 weeks gestation and continued until delivery, on the other hand, this study establishes inefficacy of the utilized regimen in impacting on maternal wellbeing. Other than improved Apgar scores observed in babies born to mothers who received vitamin D supplement, the remainder of neonatal parameters were unaffected by maternal supplementation.”
While this research shows an intriguing relationship between vitamin D supplementation during the latter half of pregnancy and improved Apgar scores, it’s also disappointing that the researchers didn’t find vitamin D to help with various conditions and complications. One possible limitation is that their study was too small to see effects beyond Apgar scores. It may also be crucial for pregnant women to supplement with vitamin D throughout pregnancy, not just during the latter half.
Continual and ongoing research should paint a clearer picture of how and in what ways adequate vitamin D supplementation during pregnancy can help with pregnancy and offspring outcomes.
Hossain N et al. Obstetric and neonatal outcomes of maternal vitamin D supplementation: Results of an open label randomized controlled trial of antenatal vitamin D supplementation in Pakistani women. The Journal of Clinical Endocrinology and Metabolism, 2014.