Concerns›Women

Pregnancy & prenatal

Check what applies to you and the best-matched supplements move to the top.

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Bottom line

For pregnancy & prenatal, start with Folate, Omega-3, Iron. The first one to look at is Folate — 400–1,000 mcg a day (counting what's in your multivitamin); Every day from 1–3 months before pregnancy through week 12.

Supplements ranked for this concern

AWell researchedBSome evidenceCLimited evidence
#SupplementEvidenceWhenHow muchCaution
1 Folate
Essential while the baby's neural tube forms in early pregnancy, so it's a nutrient to start while you're still trying to conceive.
 A Every day from 1–3 months before pregnancy through week 12 400–1,000 mcg a day (counting what's in your multivitamin) If you take seizure medicine or have had a baby with a neural tube defect, you may need a higher dose. Talk to your doctor. Compare products
2 Omega-3
DHA supports the baby's brain and eye development. Studies found that taking it with EPA was linked to lower risk of preterm birth and postpartum depression.
 A Right after a meal, starting around week 12, and keep going while breastfeeding About 1,000 mg of EPA+DHA (at least 300 mg of DHA a day; avoid high doses) Some doctors pause it around week 34 because of concerns about bleeding after birth. Follow your doctor's advice. Compare products
3 Iron
Your blood volume grows during pregnancy, so you need much more iron. Low iron has been linked to preterm birth and low birth weight.
 A From week 16 until 3 months after birth. On an empty stomach, or right after a meal if it upsets your stomach. About 25–30 mg a day on average (if you've been diagnosed with anemia, follow your doctor's prescription) If you get constipated, choose a form less likely to cause it, such as heme iron. Compare products
4 Vitamin D
Lots of data link it to preterm birth, fetal growth and blood pressure control in pregnancy. It also helps you absorb calcium.
 B Starting 2–3 months before pregnancy, right after breakfast or lunch About 2,000 IU a day (don't go over 4,000 IU while pregnant) Add up what's in your multivitamin and any calcium-magnesium-vitamin D combo so you don't double up. Compare products
5 Calcium
After week 20 the baby's bones grow fast and need lots of calcium. After birth, calcium is drawn from the mother's bones.
 B From around week 20 through after birth, split up after meals 300–400 mg a day from supplements Calcium and iron compete for absorption when taken together. Take them at different times. Compare products
6 Prenatal multivitamin
One prenatal multivitamin with active folate, B12 and iron can cover your basic nutrients evenly.
 B After a meal About 2 capsules a day of a prenatal product (check that iron is 35 mg or less) Avoid high-dose vitamin A (retinol), and check for overlap with any separate folate or iron you take. Compare products
7 Probiotics
A basic for managing constipation in pregnancy. Some strains (HN001) have data showing less eczema and atopic skin in babies.
 B Consistently, at a convenient time such as before breakfast 5–10 billion CFU a day If constipation keeps up, ask your OB-GYN about medicines that are safe in pregnancy. Compare products
8 Magnesium
Helps relieve muscle tightness, numbness and headaches before and after pregnancy. There's data suggesting it may help with postpartum low mood and sleep problems.
 B After a meal. If sleep is the issue, after dinner. 300–350 mg a day (a calcium-magnesium-vitamin D combo is OK too) If you have kidney disease, talk to your doctor first. Compare products

Medications to watch out for

If you take any medication, talk to your doctor or pharmacist before starting.

Anticonvulsants (epilepsy medicine)FolateYour folate needs may change. Set the dose with your doctor.
Blood thinners such as aspirin and warfarin (Coumadin)Omega-3May make you bleed more easily. Talk to your doctor before taking high doses.
Thyroid medicine (levothyroxine/Synthroid)CalciumReduces absorption of the drug. Space them at least 1 hour apart.
AntibioticsIron · Calcium · ProbioticsThey can block each other's absorption or weaken the probiotic. Space them at least 2 hours apart.

Before supplements: daily habits

  1. 01If you're planning a pregnancy, start folate and vitamin D at least 1–3 months ahead.
  2. 02Bring a list of your supplements to your OB-GYN visit and have it checked.
  3. 03Taking a multivitamin plus single supplements makes it easy to double up on folate, iron and vitamin A. Add up the labels.
  4. 04Take iron with water, at a different time from coffee or green tea.
  5. 05For constipation, first add more water and fiber, then add a probiotic.

Product comparison

ProductFormPer servingCountCost per day
Folic Acid 400 mcg (665 mcg DFE)Best value
Nature Made
 Folic acid, tablets1 tablet: folic acid 400 mcg (665 mcg DFE)250 Low Amazon →
Folic Acid 400 mcg
21st Century
 Folic acid, tablets1 tablet: folic acid 400 mcg (667 mcg DFE)250 Low Amazon →
Folic Acid 800 mcg with Vitamin B-12 25 mcg
NOW Foods
 Folic acid + cyanocobalamin, tablets1 tablet: folic acid 800 mcg (1,360 mcg DFE) + B12 25 mcg250 Low Amazon →
Folic Acid 800 mcg
Nature's Bounty
 Folic acid, tablets1 tablet: folic acid 800 mcg (1,333 mcg DFE)250 Low Amazon →
BioActive Folate & Vitamin B12
Life Extension
 Active L-methylfolate + methylcobalamin, capsules1 capsule: active folate 400 mcg (680 mcg DFE) + B12 300 mcg90 Average Amazon →
Optimized Folate (L-Methylfolate) 1,700 mcg DFE
Life Extension
 Active L-methylfolate calcium salt, tablets1 tablet: active folate 1,000 mcg (1,700 mcg DFE)100 Average Amazon →
Methyl Folate 1,000 mcg
NOW Foods
 Active 5-MTHF (Quatrefolic), tablets1 tablet: active folate 1,000 mcg (1,700 mcg DFE)90 Average Amazon →
Methyl B-12 1000 mcg & Methyl Folate 400 mcg plus P-5-P (Lemon, Chewable)
Jarrow Formulas
 Active 5-MTHF + methyl B12 + P5P, chewable tablets1 tablet: active folate 400 mcg (680 mcg DFE) + B12 1,000 mcg + B6 (P5P) 1.5 mg100 Average Amazon →

Compare all Folate products →

Cost per day is relative — compared with other products of the same supplement. Check Amazon for the current price. Some links are affiliate links.

Several ingredients in one pill: Compare prenatal vitamins →

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