Can You Take Prenatal Vitamin and Vitamin D3 Together?

Dose or timing may matter

The short answer

Prenatal vitamins typically contain 400-1000 IU vitamin D. Additional vitamin D3 supplementation may be necessary if deficient, but unmonitored high-dose stacking can lead to hypercalcemia and potential harm during pregnancy.

How to arrange timing

Have vitamin D levels tested before adding extra D3 to a prenatal regimen. Total intake should generally not exceed 4,000 IU/day without medical supervision.

Reference

Reference noted for this combination: Hollis BW et al. Vitamin D supplementation during pregnancy: double-blind, randomized clinical trial. J Bone Miner Res. 2011;26(10):2341-2357

Important context

Whether supplements suit you together also depends on dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.