Sufficient Preconception Vitamin D Tied to Lower Miscarriage Risk
However, increased vitamin D levels in early pregnancy not correlated with reduced pregnancy loss.
HealthDay News — Preconception vitamin D levels may play a role in maintaining pregnancy, according to a study published recently in The Lancet Diabetes & Endocrinology.
Sunni Mumford, PhD, from the National Institutes of Health in Bethesda, Md., and colleagues conducted a secondary analysis of data from the EAGeR trial to assess the association between preconception vitamin D and pregnancy outcomes among 1191 women with proven fecundity. Serum 25-hydroxyvitamin D was measured preconception (baseline) and at 8 weeks gestation.
The researchers found that 555 women (47%) were classified as having sufficient concentrations (≥75 nmol/L) while 636 (53%) had insufficient concentrations (<75 nmol/L). Clinical pregnancy was more likely among women with sufficient preconception 25-hydroxyvitamin D (adjusted risk ratio [RR], 1.10) and livebirth (adjusted RR, 1.15) versus women with insufficient concentrations. Among women who achieved pregnancy, sufficient preconception 25-hydroxyvitamin D was associated with reduced risk of pregnancy loss (preconception RR per 25 nmol/L, 0.88; 95% confidence interval, 0.77 to 0.99); but this was not found at 8 weeks of gestation (RR, 0.98; 95% confidence interval, 0.95 to 1.01).
"These results provide valuable insight into the potential effects of vitamin D during the preconception period for fertile or subfertile couples attempting spontaneous conception," the authors write.