Research paper
Vitamin D Supplementation and the Effects on Glucose Metabolism During Pregnancy: A Randomized Controlled Trial
Study answer
What this study found
High-dose vitamin D3 did not improve maternal glucose metabolism during pregnancy compared with 400 IU/day. At 26-28 weeks, fasting glucose was 75 (7) mg/dL vs 75 (6) mg/dL, 2-hour glucose was 108 (25) mg/dL vs 111 (28) mg/dL, HOMA-IR was 1.0 (1.3) vs 0.8 (1.6), and gestational diabetes occurred in 7 (8%) vs 12 (13%) participants, P = 0.25. High-dose supplementation did increase neonatal cord blood 25OHD to 46 (19) ng/mL versus 29 (12) ng/mL and reduced cord plasma 25OHD <20 ng/mL to 5 (10%) versus 11 (24%). The authors concluded that 5,000 IU/day safely improved vitamin D status and reduced…
- Study & population
- Randomized controlled trial conducted at a single institution in Sydney, Australia, enrolling pregnant women with singleton pregnancies who started supplementation before 20 weeks' gestation and had low baseline vitamin D status.
- Intervention
- Pregnant participants received oral vitamin D3 capsules daily until delivery: high dose 5,000 IU/day versus low dose 400 IU/day.
- Key limitation
- The trial was not powered to detect differences in gestational diabetes incidence, limiting inference for that outcome.
View source
Open PDFOriginal abstract
OBJECTIVE Vitamin D deficiency in pregnancy is associated with an increased risk of gestational diabetes mellitus (GDM) and neonatal vitamin D deficiency. We conducted a double-blind, randomized controlled trial of low-dose (LD) versus high-dose (HD)…