Vitamin D regulates key target genes associated with trophoblast implantation and invasion, as well as plays an important role in inducing T-helper 2-dominated immune responses that are critical for successful pregnancy. In addition, vitamin D has immune-modulating and anti-inflammatory effects that are important for preventing microbial invasion into the intrauterine.
It is estimated that 18%-74% of pregnant women in the world have vitamin D deficiency (blood levels of 25(OHD) <30 ng/mL), and 99.6% of pregnant women in the first trimester in Jakarta have vitamin D deficiency and insufficiency. Vitamin D deficiency in pregnant women is associated with poor pregnancy outcomes, such as preterm labor, preeclampsia, gestational diabetes, and stunted fetal growth.
Institute of Medicine Report in 2010, the recommended daily supplement of vitamin D during pregnancy is 600 IU, but this dose may not be enough to maintain vitamin D sufficiency in pregnant women. Recent research suggests that pregnant women should take 4,000 IU/day of vitamin D3 starting at 12-16 weeks of gestation to achieve vitamin D sufficiency. The Endocrine Society Clinical Practice Guideline recommends treating vitamin D deficiency in adults with 50,000 IU of vitamin D3 once a week for 8 weeks, or a daily dose equivalent to 6,000 IU of vitamin D3 to achieve blood levels of 25(OH)D above 30 ng/mL.
A randomized controlled trial (RCT) conducted by Syafitri, et al, (2024) evaluated the effect of different vitamin D3 administration on vitamin D metabolite concentrations in pregnant women with gestational age ≤14 weeks with vitamin D deficiency or insufficiency ((25(OH)D <30 ng/mL). The intervention group was randomized to a dose of 5,000 IU vitamin D3 daily or 50,000 IU weekly.
In the 50,000 group, 25(OH)D levels increased significantly from 15.3 ± 4.7 ng/mL to 26.9 ± 6.1 ng/mL (p < 0.001) and 34.6% of subjects reached the vitamin D sufficiency level, while in the 5. 000 IU of vitamin D, 25(OH)D levels also increased significantly from 14.5 ± 4.3 ng/mL to 27.9 ± 9.3 ng/mL (p < 0.001) and 23.1% of subjects reached vitamin D sufficiency. Both groups showed an increasing trend in total 25(OH)D levels but the increase in all vitamin D metabolites was not significantly different between the two groups.
Conclusion:
This study showed that weekly administration of 50,000 IU vitamin D3 is as effective and safe as daily administration of 5,000 IU vitamin D in increasing vitamin D levels in pregnant women with vitamin D deficiency or insufficiency.
Image: Illustration (Source: Jonathan Borba-Pexels)
Reference:
Syafitri I, Irwinda R, Saroyo Y, Purwosunu Y, Wibowo N. Maternal concentrations of vitamin D metabolites in response to high-dose oral vitamin D during first-trimester pregnancy: A randomized controlled trial. Res Squ [Internet]. 2024. Available from: https://ouci.dntb.gov.ua/en/works/735GYxXl/.
