Coenzyme Q10
Other supplementAlso called · 3 names▾▴
CoQ10, Co Q10, ubiquinone
Coenzyme supplement
Herbs and supplements are not FDA-approved before sale. About these sources
- Other
Research strength: 1 / 5
According to the German Federal Institute for Risk Assessment (BfR), studies on CoQ10 supplements during pregnancy are insufficient; it advises avoiding products with relevant daily doses or consulting a health professional before use. A 2009 randomized trial assigned 235 women at increased risk of pre-eclampsia to 200 mg daily CoQ10 or placebo from week 20 until delivery, so it did not test first-trimester use. The trial's primary outcome was pre-eclampsia, and its abstract does not report birth-defect or miscarriage results. A 2025 review calls the trial small and says CoQ10 is not currently recommended for pre-eclampsia prevention. BfR's data-gap assessment and the trial's week-20 start leave effects from first-trimester supplement use undetermined. Ask your provider about your situation.
Last reviewed: 2026-10-16
Research strength: 2 / 5
According to the BfR, studies on CoQ10 supplements during pregnancy are insufficient; it advises avoiding products with relevant daily doses or consulting a health professional before use. One randomized trial enrolled 235 women at increased risk of pre-eclampsia and assigned 200 mg daily CoQ10 or placebo from week 20 through delivery; 197 women were followed. The study reported pre-eclampsia in 17 of 118 women (14.4%) assigned CoQ10 and 30 of 117 (25.6%) assigned placebo. The 2025 review calls the trial small and says CoQ10 is not currently recommended to prevent pre-eclampsia; the trial abstract does not establish birth-defect, miscarriage, or other newborn outcomes. Ask your provider about your situation.
Last reviewed: 2026-10-16
Research strength: 2 / 5
According to the BfR, studies on CoQ10 supplements during pregnancy are insufficient; it advises avoiding products with relevant daily doses or consulting a health professional before use. One randomized trial enrolled 235 women at increased risk of pre-eclampsia and assigned 200 mg daily CoQ10 or placebo from week 20 through delivery; 197 women were followed. The study reported pre-eclampsia in 17 of 118 women (14.4%) assigned CoQ10 and 30 of 117 (25.6%) assigned placebo. The 2025 review calls the trial small and says CoQ10 is not currently recommended to prevent pre-eclampsia; the trial abstract does not establish birth-defect, miscarriage, or other newborn outcomes. Ask your provider about your situation.
Last reviewed: 2026-10-16
Coenzyme Q10 — Breastfeeding
Research strength: 2 / 5
LactMed reports that CoQ10 is a normal component of human milk, but milk levels have not been measured after a mother's supplement use. LactMed found no published information about effects in breastfed infants or milk production after supplementation. A study of 25 healthy full-term newborns compared 15 breast-fed and 10 formula-fed babies by measuring blood CoQ10; it did not test maternal supplements or clinical infant effects. The BfR says evidence about supplementation during breastfeeding is insufficient and advises avoiding products with relevant daily doses or consulting a health professional first. LactMed and BfR's evidence-gap assessments leave the effects of supplemental CoQ10 on milk or infant outcomes undetermined. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- LactMed: Coenzyme Q10US government
- BfR: Coenzyme Q10 health risks FAQ
- Compagnoni et al. 2004: CoQ10 levels in breast-fed and formula-fed infantsUS government
- Mayo Clinic: Coenzyme Q10
Pregnancy
A 2009 randomized, double-blind, placebo-controlled trial enrolled 235 women at increased risk of pre-eclampsia and assigned 118 to CoQ10 200 mg daily and 117 to placebo from 20 weeks of pregnancy until delivery. Follow-up was available for 197 women (83.8%). Pre-eclampsia occurred in 17/118 women assigned CoQ10 (14.4%) and 30/117 assigned placebo (25.6%; P=0.035; relative risk 0.56, 95% CI 0.33-0.96). The abstract identifies pre-eclampsia as the primary outcome and does not report results for birth defects or miscarriage. A 2025 review describes this as one small trial, notes that larger trials are needed, and says CoQ10 supplementation is not currently recommended for pre-eclampsia prevention. The 2026 studies located focused on fertility treatment or preconception supplementation; they do not establish outcomes from continued use during pregnancy.
Breastfeeding
LactMed reports that CoQ10 is present naturally in human milk, but milk levels have not been measured after maternal supplement use. It reports no published information about effects in breastfed infants or milk production as of its May 2021 revision. Primary studies measured naturally occurring milk CoQ10 or infant blood levels, not outcomes after maternal supplementation. Niklowitz et al. measured milk and plasma levels in 23 women during the first 14 days after birth. Compagnoni et al. prospectively measured 25 healthy term newborns, including 15 breast-fed and 10 formula-fed infants, during the first month; the study compared blood CoQ10 levels and did not test maternal supplementation or clinical effects. BfR also reports insufficient studies on supplement effects in breastfeeding women and children.
Coenzyme Q10, also called ubiquinone, is a substance the body makes and that occurs in foods. BfR says it is not an essential nutrient because the body normally produces enough. Supplements are sold as ubiquinone or ubiquinol, in different amounts and as single-ingredient or combination products. BfR does not consider additional supplements necessary for healthy people eating a varied diet and gives no general supply recommendation for a population group.
What was tested
Pregnancy evidence includes one small randomized trial of 200 mg/day CoQ10 started at 20 weeks in women at increased risk of pre-eclampsia; it measured pre-eclampsia, not a broad set of fetal outcomes. A 2026 randomized fertility-treatment study included 100 women with poor ovarian response; 50 received CoQ10 plus folic acid for one month before and during ICSI and 50 received folic acid alone. Its primary outcome was oocyte count, and pregnancy rates were secondary outcomes; it was not designed to assess continued supplement use during pregnancy. Breastfeeding studies assessed naturally occurring milk concentrations or blood CoQ10 in infants, not maternal supplement exposure. LactMed reports that human milk levels have not been measured after maternal CoQ10 supplementation; the published lactation studies measured baseline milk or infant levels.
How to interpret the one pregnancy trial that reported fewer cases of pre-eclampsia
- Source A says
- The 2009 randomized trial reported fewer cases of pre-eclampsia in the group assigned CoQ10 200 mg daily from week 20 through delivery than in the placebo group. (Teran et al. 2009: Coenzyme Q10 supplementation during pregnancy reduces the risk of pre-eclampsia)
- Source B says
- BfR says studies of supplemental CoQ10 effects in pregnancy are insufficient and advises avoiding products with relevant daily doses or consulting a health professional. The 2025 review says the trial was small and CoQ10 is not currently recommended to prevent pre-eclampsia. (German Federal Institute for Risk Assessment (BfR): Coenzyme Q10 health risks FAQ, Ushida et al. 2025: Dietary supplements and prevention of preeclampsia)
- Why they differ
- The trial tested a specific possible benefit in a selected group at higher risk, from week 20 through delivery. BfR and the review focus on whether the evidence is enough to support use more broadly. The trial does not establish birth-defect, miscarriage, or other newborn outcomes.
- What the evidence shows overall
- The trial is a limited efficacy finding in a specific group, not enough to establish broader pregnancy use or effects on fetal and newborn outcomes. The evidence gap described by BfR supports an insufficient rating.
- BfR says pregnant and breastfeeding people should avoid products with relevant daily doses or consult a physician or other health professional before use because studies are insufficient. (German Federal Institute for Risk Assessment (BfR))
- Mayo Clinic says it has not been decided whether CoQ10 supplements are appropriate during pregnancy or breastfeeding and calls for professional approval before use. (Mayo Clinic)
General research, not specific to pregnancy.
BfR reports occasional digestive effects and isolated skin rashes in studies using doses up to 300 mg per day, and says effects above that amount have not been investigated. NCCIH lists possible interactions with warfarin and insulin and says CoQ10 may not work with some types of cancer treatment.
- BfR reports nausea, heartburn, stomach discomfort, diarrhea, and isolated skin rashes in some studies at doses up to 300 mg per day; effects above 300 mg per day have not been investigated. (German Federal Institute for Risk Assessment (BfR): Coenzyme Q10 health risks FAQ)
- NCCIH says CoQ10 may interact with warfarin and insulin and may not be compatible with some types of cancer treatment. (NCCIH: Coenzyme Q10)
- LactMed: Coenzyme Q10US governmentSecondaryPage dated 2021-05-17
- NCCIH: Coenzyme Q10US governmentSecondary
- German Federal Institute for Risk Assessment (BfR): Coenzyme Q10 health risks FAQSecondaryPage dated 2023-11-10Independent check
- Mayo Clinic: Coenzyme Q10SecondaryPage dated 2025-05-22Independent check
- Teran et al. 2009: Coenzyme Q10 supplementation during pregnancy reduces the risk of pre-eclampsiaUS governmentPrimaryIndependent check
- Ushida et al. 2025: Dietary supplements and prevention of preeclampsiaUS governmentPrimaryIndependent check
- Niklowitz et al. 2005: Coenzyme Q10 in maternal plasma and milk throughout early lactationUS governmentPrimaryIndependent check
- Compagnoni et al. 2004: CoQ10 plasma levels in breast-fed and formula-fed infantsUS governmentPrimaryIndependent check
- Tang et al. 2006: Determination of coenzyme Q10 in human breast milkUS governmentPrimaryIndependent check
- Abdelrahman et al. 2026: Coenzyme Q10 and ICSI outcomes in poor ovarian respondersUS governmentPrimary
- Mutlu Özmen et al. 2026: CoQ10 supplementation before IVF in women with PCOSUS governmentPrimary
- Castillo-Castrejon et al. 2026: CoQ10 and obesity-associated reproductive dysfunctionUS governmentPrimary
Last reviewed 2026-10-16
Independent check 2026-10-16
Not yet clinician-reviewed
Ask your provider about your situation.