What do medical sources say about Vitamin B6 during pregnancy?

1st Trimester: NIH ODS lists 1.9 mg/day as the recommended vitamin B6 intake during pregnancy. ACOG includes B6 as an early nausea treatment; ODS reports its dose as 10 to 25 mg three or four times daily, with doxylamine added if symptoms do not improve. Vutyavanich et al. (1995) found less nausea with 30 mg/day in 342 women, while Sahakian et al. (1991) found a benefit only in the severe-nausea group; a Cochrane review found the evidence limited. ODS notes isolated birth-defect case reports; a small 2006 study found one major malformation among 96 pregnancies exposed to more than 50 mg/day, with no significant difference from controls. The U.S. adult upper limit is 100 mg/day, while EFSA sets 12 mg/day for adults, including pregnancy; that disagreement concerns higher intake, not the usual nutrient amount. Ask your provider about your situation. 2nd Trimester: NIH ODS lists 1.9 mg/day as the recommended vitamin B6 intake during pregnancy. ACOG's nausea-treatment dose, as reported by ODS, is 10 to 25 mg three or four times daily, which is different from routine nutritional intake. The pregnancy trials enrolled women in early pregnancy, and the high-dose birth-outcome study examined first-trimester exposure; they do not give a separate result for usual intake in the second trimester. The U.S. adult upper limit is 100 mg/day, while EFSA sets 12 mg/day for adults, including pregnancy; this difference concerns higher intake, not the recommended amount. Ask your provider about your situation. 3rd Trimester: NIH ODS lists 1.9 mg/day as the recommended vitamin B6 intake during pregnancy. ACOG's nausea-treatment dose, as reported by ODS, is 10 to 25 mg three or four times daily, which is different from routine nutritional intake. The pregnancy trials enrolled women in early pregnancy, and the high-dose birth-outcome study examined first-trimester exposure; they do not give a separate result for usual intake in the third trimester. The U.S. adult upper limit is 100 mg/day, while EFSA sets 12 mg/day for adults, including pregnancy; this difference concerns higher intake, not the recommended amount. Ask your provider about your situation.

Where do sources disagree on Vitamin B6 in pregnancy or breastfeeding?

Adult upper limits and nausea-treatment doses The U.S. FNB sets an adult UL of 100 mg/day, including pregnancy and lactation. ODS reports ACOG's NVP regimen as 10 to 25 mg three or four times daily and says the U.S. UL does not apply to medical treatment under physician care. LactMed says 100 to 200 mg/day disease-treatment doses have not been studied during lactation. EFSA's 2023 opinion sets a UL of 12 mg/day for adults, including pregnant and lactating people, based on evidence about peripheral neuropathy. The U.S. FNB set its UL by halving an average 200 mg/day dose used in studies for up to 5 years because long-term harm data were limited. EFSA used 50 mg/day as a reference point and applied an uncertainty factor of 4 for limited data and earlier symptom onset at lower doses. ACOG's higher regimen is a treatment for pregnancy nausea, while ULs and NHS public advice concern general supplemental intake. ODS says the U.S. UL does not apply to medical treatment and that such treatment belongs under physician care. The recommended amount is 1.9 mg/day in pregnancy and 2 mg/day during lactation, below the cited adult limits. A higher nausea regimen is treatment, not routine nutrition. The sources disagree on the adult UL, and excess supplemental intake is linked with peripheral neuropathy; the disagreement does not establish harm at usual nutrient amounts.

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Vitamin B6

Q: What do medical sources say about Vitamin B6 while breastfeeding?

LactMed reports that vitamin B6 is present in human milk and that maternal supplements raise milk levels; NIH ODS lists 2 mg/day as the recommended intake during lactation. Heiskanen et al. (1995) found low B6 levels in 7 of 44 healthy breastfed infants at 4 to 6 months; slower growth from 6 to 9 months was no longer seen by 10 to 12 months. Heiskanen et al. (1996) found low infant B6 levels became more common when exclusive breastfeeding continued beyond 6 months, but did not prove that maternal intake caused the low levels. LactMed says 7.5 to 20 mg/day used to prevent or treat maternal deficiency should provide enough B6 through milk, while 100 to 200 mg/day treatment doses have not been studied during lactation. The U.S. adult upper limit is 100 mg/day, while EFSA sets 12 mg/day; those limits differ from the 2 mg recommended amount. Ask your provider about your situation.

Vitamin & mineral

Also called · 7 names▾

pyridoxine, pyridoxal, pyridoxamine, pyridoxal 5-phosphate, pyridoxamine 5-phosphate, PLP, PMP

Vitamin supplement

Herbs and supplements are not FDA-approved before sale. About these sources

Capsule/tablet

Pregnancy

NIH ODS reports mixed results from two randomized, placebo-controlled trials of pyridoxine for nausea and vomiting of pregnancy. Vutyavanich et al. (1995) randomized 342 women at 17 weeks' gestation or earlier to 30 mg/day or placebo for 5 days: nausea improved more with pyridoxine (p = 0.0008), while the vomiting difference did not reach statistical significance (p = 0.0552). Sahakian et al. (1991) reported 59 women who completed the trial: 31 received 25 mg every 8 hours for 72 hours and 28 received placebo. Nausea improved more in the severe-nausea subgroup, but not in the mild-to-moderate group or the full group; vomiting at the end of treatment was reported in 8/31 versus 15/28 participants (p < 0.05). The 2015 Cochrane review included 41 trials with 5,449 women across interventions and found only limited evidence for vitamin B6 or other medicines for mild-to-moderate symptoms. ODS reports that ACOG recommends 10 to 25 mg three or four times daily for NVP, adding doxylamine if symptoms do not improve. This is a treatment regimen, not the 1.9 mg/day pregnancy RDA. The ACOG FAQ supports B6 as a first option but does not show the numerical dose. The CDC Yellow Book (2025 page, 2026 edition) also says pyridoxine reduces morning-sickness symptoms. For higher-dose exposure, ODS notes isolated case reports of congenital defects in the first half of pregnancy. Shrim et al. (2006) followed 96 pregnancies exposed to more than 50 mg/day in trimester one and 96 control pregnancies; the mean exposed dose was 132.3 mg/day (median 110, range 50 to 510) for 9 +/- 4.2 weeks. The exposed group had 91 live births and one major malformation, with no statistically significant difference in study endpoints versus controls. This small, nonrandomized study cannot rule out uncommon outcomes. EFSA's 2023 opinion says excess B6 intake is linked to peripheral neuropathy and sets an adult UL of 12 mg/day, including pregnancy. Recent evidence: Cho et al. (2025) included 630,904 children, with 131,837 prenatal pyridoxine exposures in secondary analyses. The abstract reports no substantial association between antiemetic exposure and child neurodevelopmental disorders or delays overall, but gives no pyridoxine-specific effect estimate. Gao et al. (2026) analyzed 352 women with NVP at 12 weeks or earlier; higher serum PLP was associated with faster natural symptom resolution (adjusted HR 0.60 for the highest versus lowest quartile, 95% CI 0.42 to 0.86). This was not a supplement trial. Frivaldszky et al. (2026) synthesized 24 randomized trials with 3,017 participants; the highlighted B6 intervention combined B6 with pomegranate and mint, and evidence quality was low to moderate with limited adverse-event reporting. It does not establish the effect of B6 alone.

Breastfeeding

LactMed reports that vitamin B6 is naturally present in human milk and that maternal supplementation raises milk levels in a dose-dependent way. It lists 2 mg/day as the minimum maternal intake and says 7.5 to 20 mg/day used to prevent or treat deficiency should provide an adequate amount for an exclusively breastfed infant; lower doses may not do so if the mother has underlying deficiency. It says 100 to 200 mg/day used for some B6-responsive diseases have not been studied during lactation. Kang-Yoon et al. (1992) randomized 20 postpartum women to 2 or 27 mg/day for 28 days. At day 28, mean milk B6 levels were 700 nmol/L in the 2 mg group and 3,200 nmol/L in the 27 mg group; infant B6 intake and status reflected maternal intake. Borschel et al. (1986) studied healthy term infants whose mothers received 2.5 or 15 mg/day. Growth was similar to formula-fed infants and within normal ranges through 6 months, but breastfed infants had lower plasma PLP than formula-fed infants; the lowest values were in infants of mothers receiving 2.5 mg/day. The long-term meaning of those PLP differences was uncertain. Heiskanen et al. (1995) followed 44 healthy breastfed infants; 7 had low B6 status at 4 to 6 months and then slower length growth from 6 to 9 months than infants with higher status. LactMed reports no difference by 10 to 12 months. Heiskanen et al. (1996) followed exclusively breastfed infants at multiple ages; all mothers received 1 mg/day during lactation. Low infant B6 status became more common as exclusive breastfeeding continued beyond 6 months, but the study did not establish that maternal intake caused the lower levels. Guala et al. (2022) reported one newborn with tremors and a high serum B6 level after maternal prenatal vitamin use containing 4 mg/day. LactMed notes that the infant had breastfed once before symptoms and likely had placental exposure rather than a milk-related exposure. This case does not establish an effect from breastfeeding. A 2026 study of premature infants born below 1,500 g found lower PLP in exclusively breastfed than formula-fed infants, but it studied a specific preterm, very-low-birth-weight population and did not test maternal B6 supplements.

Last reviewed 2026-10-16

Independent check 2026-10-16

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Vitamin B6

Vitamin B6 — Breastfeeding

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