June 10, 2026 Updated on October 06, 2026
When should you start prenatal vitamins?
When should you start prenatal vitamins?
The ideal time to start is at least three months before you begin trying to conceive. Six months is even better. Here's why: the neural tube closes within the first 28 days after conception, often before a missed period. Folate needs to be circulating in adequate amounts in your blood before that window opens to support optimal neural tube health and reduce the risk of a neural tube defect.
RELATED: How to choose a prenatal vitamin
The science behind early supplementation
Research on red blood cell folate concentrations shows that it takes approximately three to six months of consistent supplementation to reach the optimal threshold associated with the lowest risk of neural tube defects. The U.S. Preventative Services Task Force (USPSTF) classifies daily folate supplementation for all women planning or capable of pregnancy as a Grade A recommendation.
Additionally, iron stores, vitamin D levels, and choline all benefit from early replenishment. Starting early means your body has strong nutrient reserves when the demands of pregnancy begin, rather than playing catch-up.
WeNatal For Her
24 key nutrients for healthy pre-pregnancy, pregnancy, and postpartum.
What if you didn't start a prenatal before conception?
Start now. Whenever you find out you're pregnant, begin taking a comprehensive prenatal vitamin immediately. While earlier is better for neural tube protection specifically, prenatal vitamins offer benefits throughout every stage of pregnancy: supporting red blood cell production, fetal bone growth, brain development, and placental health.
No guilt and no panic. The body is remarkably adaptable, and starting prenatals at any point is better than not taking them at all.
Don't forget about him
Sperm takes approximately 70-90 days to fully develop. Therefore, the quality of sperm at the point of conception reflects the nutrition and lifestyle from about three months prior. For couples trying to conceive, both partners starting their supplements three to six months before is the optimal approach.
RELATED: Prenatal vitamins for men: A guide to supporting sperm health
A note from WeNatal on when to start
WeNatal for Her was designed to be the prenatal you start before you conceive. With methylfolate, iron, choline, and vitamin D3 at science-backed levels, it gives your body the time it needs to build real nutrient reserves. WeNatal for Him supports the male side of the equation with CoQ10, zinc, selenium, and methylfolate for optimal sperm health. Starting early is one of the simplest, most proactive steps a couple can take together.
RELATED: The ultimate preconception guide: What to do when you're ready to get pregnant
References
Barry MJ, et al. (2023). Folic acid supplementation to prevent neural tube defects: USPSTF reaffirmation recommendation statement. JAMA, 330(5):454-459. DOI: 10.1001/jama.2023.12876
Viswanathan M, Urrutia RP, Hudson KN, et al. Folic Acid Supplementation to Prevent Neural Tube Defects: A Limited Systematic Review Update for the U.S. Preventive Services Task Force [Internet]. Rockville (MD): Agency for Healthcare Research and Quality (US); 2023 Aug. (Evidence Synthesis, No. 230.) Chapter 1, Introduction. Available from: https://www.ncbi.nlm.nih.gov/books/NBK593617/
