Vitamin B12

Do you need more vitamin B12 in pregnancy?

Updated 3 Nov 2026

Short answer

A little more: the US amount rises from 2.4 µg a day to 2.6 µg in pregnancy and 2.8 µg while breastfeeding.[1] A 2024 Cochrane review of 5 trials found that supplements may lower the share of mothers with a deficiency: 25.9% against 67.9%. The evidence was very uncertain, and effects on the baby were not clear.[2] Babies breastfed by mothers who eat no animal foods are at risk of a deficiency.[1]

Sources (2)

  1. Vitamin B12: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. ods.od.nih.gov
  2. Vitamin B12 supplementation during pregnancy for maternal and child health outcomes. Finkelstein JL, Fothergill A, Venkatramanan S, Layden AJ, Williams JL, Crider KS, et al. Cochrane Database Syst Rev, 2024. PMID 38189492

More about vitamin b12

What is vitamin B12?Who is likely to be low in vitamin B12?What is vitamin B12 used for?Which foods contain vitamin B12?Is vitamin B12 safe?How long does vitamin B12 take to work?

For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.