Does vitamin E improve fertility?

Unproven. In a Cochrane review of antioxidants for subfertile men, vitamin E among them, live births rose with an odds ratio of 1.43 across 12 trials and 1,283 men, on very low-certainty evidence. When the trials at high risk of bias were removed, the odds ratio fell to 1.22 and was no longer significant. The largest single placebo-controlled trial we found, of an antioxidant mix containing vitamin E in 174 men, found 15% live births against 24% on placebo, a difference that was not significant.

Unsettled. The evidence leans faintly positive only where it is weakest. Small, older trials report more pregnancies. The better-run trials and the strictest recent review do not. Most of it also tests vitamin E inside a mix of antioxidants, so even a real effect could not be credited to vitamin E.

What the trials found

Men: live births and pregnancies

The Cochrane review is the largest synthesis. Its live birth analysis pooled 12 randomized trials and 1,283 men and found an odds ratio of 1.43 (95% CI 1.07 to 1.91), which the reviewers rated very low-certainty. Restricted to the 8 trials and 827 men at lower risk of bias, the odds ratio was 1.22 (95% CI 0.85 to 1.75, P = 0.27). The review pooled antioxidants together, with vitamin E as one of many.

A meta-analysis that looked at vitamin E specifically, in trials of 832 infertile men, found partners became pregnant more often, with a risk ratio of 1.86 (95% CI 1.02 to 3.41). The lower end of that interval sits close to no effect, and the authors rated the quality moderate to low. A stricter 2025 meta-analysis took only placebo-controlled trials lasting at least 12 weeks, 50 of them, and found no supplement improved pregnancy or live birth. In that review, vitamin E, vitamin D and omega-3 showed no improvement in sperm.

The single trials split. In the MOXI trial, 174 men with male factor infertility took a daily mix of seven antioxidants including vitamin E for 3 to 6 months, and cumulative live birth at 6 months was 15% against 24% on placebo. The authors note the trial was limited by its size. In a double-blind trial of 101 IVF couples, men who took 400 mg of vitamin E a day for 3 months had a live-birth rate per embryo transfer of 41.46% against 20.46% on placebo (OR 2.75, 95% CI 1.05 to 7.19). Counted per cycle started, the difference was not significant, and sperm results were no better than placebo. In a third, double-blind trial of 124 IVF couples, 400 IU a day for 8 weeks left IVF outcomes no different. Eight weeks is shorter than one cycle of sperm production, which the card puts at about 74 days.

Men: sperm counts and movement

Sperm tests are a stand-in for fertility, and vitamin E does little to them. A meta-analysis of 8 trials in 459 infertile men found no significant difference in sperm concentration (SMD 0.04, 95% CI -0.21 to 0.29) or total motility (SMD 0.20, 95% CI -0.01 to 0.42). After varicocele surgery, two randomized trials pooled in a 2026 meta-analysis found no added benefit of vitamin E for sperm concentration (SMD 0.09, 95% CI -0.59 to 0.76) or motility (SMD 0.15, 95% CI -0.19 to 0.49). A network meta-analysis of 29 trials in 2,045 men ranked vitamin E with selenium or zinc highest for total motility. A ranking is not an effect size, and that analysis reported no pregnancies.

Women

For subfertile women, a Cochrane review of antioxidants, vitamin E among them, found a live-birth odds ratio of 1.81 (95% CI 1.36 to 2.43) across 13 trials and 1,227 women, and said that because the evidence was very low quality it could not be sure antioxidants improve live birth at all. Seven of the trials in that review have since been retracted, and the editors judged the conclusions unchanged. A 2026 meta-analysis of 40 trials in infertile women found no high-certainty evidence that any dietary supplement improves fertility outcomes against placebo. Vitamin E appeared only in its weaker comparisons, as an idea to test.

Who should be careful

The doses used in these trials sit at or above the safety ceilings. The three single trials above gave 400 mg or 400 IU a day. EFSA kept its adult upper limit at 300 mg of alpha-tocopherol a day in 2024, and the card notes that 400 IU of the synthetic form is about 180 mg, so the 400 mg trials exceed that limit. The NIH Office of Dietary Supplements warns that large doses taken with warfarin or antiplatelet drugs can raise the risk of bleeding, and puts the amount needed probably above 400 IU a day.

Once a pregnancy starts, vitamin E is not harmless either. In a Cochrane review of supplements in pregnancy, vitamin E, mostly given with vitamin C, raised the risk of term prelabour rupture of membranes, with a risk ratio of 1.77 (95% CI 1.37 to 2.28) across two trials and 2,504 women. In the trials for male subfertility, antioxidants raised mild stomach upset, with an odds ratio of 2.70 (95% CI 1.46 to 4.99), on low-certainty evidence. In women, antioxidants made no difference to miscarriage (OR 1.13, 95% CI 0.82 to 1.55).

Not for everyone. If you take a blood thinner, a fertility supplement with 400 IU or more of vitamin E is a bleeding question to raise with your doctor. If you are trying to conceive, a vitamin E supplement taken into pregnancy carries a measured risk of the waters breaking before labor starts at term, in trials that mostly paired it with vitamin C.

What expert bodies say

EFSA and the NIH Office of Dietary Supplements speak to safety, as above, and neither card states a position on vitamin E for fertility. The 2020 guideline on male infertility from the American Urological Association and the American Society for Reproductive Medicine discusses supplements in its full text, which we could not read, so we do not report its position here.

More on vitamin E: the vitamin E guide and vitamin E and pregnancy outcomes.

How we searched

What would change this answer

• A placebo-controlled trial of vitamin E alone, at a dose within the upper limit, that counts live births per couple rather than per transfer and runs longer than one cycle of sperm production. Almost everything above tests mixes, short courses or sperm counts.
• The vitamin E subgroup numbers inside the two Cochrane reviews, which we could not read. If they differed from the pooled antioxidant results, the answer for vitamin E specifically would change.
• A check of trials now running. We did not search the trial registries for this pair, so we cannot say whether a trial that would settle the question is under way.

Sources

1. ev-vef-01 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of randomized controlled trials · n = 1,283 (live birth analysis, 12 RCTs)
   Live birth: antioxidants may lead to increased live birth rates (odds ratio (OR) 1.43, 95% confidence interval (CI) 1.07 to 1.91, P = 0.02, 12 RCTs, 1283 men, I2 = 44%, very low-certainty evidence).
   
   Who: subfertile men aged 18 to 65 in couples attending fertility clinics; oral antioxidants vs placebo or no treatment
   Effect: live birth OR 1.43 (95% CI 1.07 to 1.91), P = 0.02, 12 RCTs, I2 44%, very low certainty
   Certainty: Best synthesis. Pooled antioxidants, not vitamin E alone; the benefit disappears in low-risk-of-bias trials.
   Cochrane Database Syst Rev, 2022 · checked 2026-10-07 · we read the abstract
2. ev-vef-02 · Meta-analysis or systematic review · Cochrane systematic review, sensitivity analysis · n = 827
   When studies at high risk of bias were removed from the analysis, there was no evidence of increased live birth (Peto OR 1.22, 95% CI 0.85 to 1.75, 827 men, 8 RCTs, P = 0.27, I2 = 32%).
   
   Who: subfertile men in RCTs at low or unclear risk of bias
   Effect: Peto OR 1.22 (95% CI 0.85 to 1.75), P = 0.27, I2 32%
   Certainty: The live-birth signal rests on 246 births in small trials; authors call the evidence inconclusive.
   Cochrane Database Syst Rev, 2022 · checked 2026-10-07 · we read the abstract
3. ev-vef-03 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of randomized controlled trials · n = 1,355
   Gastrointestinal: antioxidants may lead to an increase in mild gastrointestinal discomfort when compared with placebo or no treatment (OR 2.70, 95% CI 1.46 to 4.99, P = 0.002, 16 RCTs, 1355 men, I2 = 40%, low-certainty evidence).
   
   Who: subfertile men in RCTs of oral antioxidants
   Effect: mild gastrointestinal discomfort OR 2.70 (95% CI 1.46 to 4.99), P = 0.002, low certainty
   Certainty: Low-certainty, low event rate (46 of 1,355).
   Cochrane Database Syst Rev, 2022 · checked 2026-10-07 · we read the abstract
4. ev-vef-04 · Meta-analysis or systematic review · meta-analysis of randomized controlled trials · n = 832
   The pregnancy rate was obviously better in the VitE group than in the control group (relative risk (RR) 1.86, 95% confidence interval (CI) 1.02-3.41).
   
   Who: infertile men in RCTs of vitamin E or vitamin C vs control
   Effect: pregnancy rate RR 1.86 (95% CI 1.02 to 3.41) for vitamin E
   Certainty: Evidence quality moderate to low per authors; lower CI bound near 1; vitamins E and C pooled for sperm outcomes.
   Int Urol Nephrol, 2022 · checked 2026-10-07 · we read the abstract
5. ev-vef-05 · Meta-analysis or systematic review · meta-analysis of randomized controlled trials · n = 459
   There were no statistically significant differences in increasing sperm concentration (95% CI: -0.21-0.29, SMD = 0.04, p = 0.769), total sperm motility (95% CI: -0.01-0.42, SMD = 0.20, p = 0.061) or sperm forward motility rate (95% CI: -0.06-0.65, SMD = 0.29, p = 0.106).
   
   Who: male infertility patients in randomized controlled trials of vitamin E
   Effect: concentration SMD 0.04 (95% CI -0.21 to 0.29); total motility SMD 0.20 (-0.01 to 0.42); forward motility SMD 0.29 (-0.06 to 0.65)
   Certainty: Sperm parameters, not pregnancy; small standardized effects.
   Urol J, 2022 · checked 2026-10-07 · we read the abstract
6. ev-vef-06 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled trials with GRADE · n = 50 RCTs
   Vitamin D, vitamin E, and omega-3 fatty acids showed no improvement in sperm parameters.
   
   Who: infertile men in RCTs of dietary supplements vs placebo for 12 weeks or more
   Effect: no effect on pregnancy and live birth; vitamin E no improvement in sperm parameters; certainty generally low or very low (GRADE)
   Certainty: Placebo-only comparisons, minimum 12 weeks; stricter than earlier reviews.
   Nutrients, 2025 · checked 2026-10-07 · we read the abstract
7. ev-vef-07 · Meta-analysis or systematic review · systematic review and meta-analysis (RCTs and cohort) · n = 408
   Pooled analysis of two randomized trials showed no significant additional benefit of vitamin E versus control for sperm concentration (SMD 0.09, 95% CI-0.59 to 0.76; p = 0.80) or sperm motility (SMD 0.15, 95% CI-0.19 to 0.49; p = 0.39).
   
   Who: men after varicocelectomy given vitamin E alone or in antioxidant combinations
   Effect: sperm concentration SMD 0.09 (95% CI -0.59 to 0.76); motility SMD 0.15 (-0.19 to 0.49); 2 RCTs pooled
   Certainty: Only two randomized trials pooled; pregnancy outcomes reported inconsistently.
   Arch Ital Urol Androl, 2026 · checked 2026-10-07 · we read the abstract
8. ev-vef-08 · Meta-analysis or systematic review · network meta-analysis of randomized controlled trials · n = 2,045
   Vitamin E+selenium or zinc had the highest SUCRA for total motility.
   
   Who: men with idiopathic oligo-astheno-teratozoospermia, mean age 33.5
   Effect: highest SUCRA for total motility: vitamin E plus selenium or zinc; no pregnancy outcomes
   Certainty: Ranking, not an effect size; semen parameters are surrogates for fertility.
   Andrology, 2024 · checked 2026-10-07 · we read the abstract
9. ev-vef-09 · Randomized controlled trial(s) · multicentre double-blind randomized placebo-controlled trial · n = 174
   In the entire cohort, cumulative live birth did not differ at 6 months between the antioxidant and placebo groups: 15% versus 24%.
   
   Who: men with male factor infertility at 9 US fertility centers; partners ovulatory, 40 or younger
   Effect: cumulative live birth at 6 months 15% antioxidant vs 24% placebo (NS); no difference in morphology, motility or DNA fragmentation
   Certainty: Mix of 7 antioxidants (vitamin C 500 mg, vitamin E 400 mg, selenium, L-carnitine, zinc, folic acid, lycopene); limited by sample size.
   Fertil Steril, 2020 · checked 2026-10-07 · we read the abstract
10. ev-vef-10 · Randomized controlled trial(s) · double-blind randomized placebo-controlled trial · n = 124
    Furthermore, the IVF outcomes of the two groups were not different significantly, either.
    
    Who: infertile couples in an IVF program; men with idiopathic abnormal motility or morphology; 61 vitamin E, 63 placebo
    Effect: no significant change in volume, count, motility, morphology; IVF outcomes not different
    Certainty: Short course (8 weeks), shorter than one sperm cycle of about 74 days.
    Biomed Res Int, 2021 · checked 2026-10-07 · we read the abstract
11. ev-vef-11 · Randomized controlled trial(s) · double-blind randomized placebo-controlled trial · n = 101
    The live-birth rate per transfer was statistically significantly higher in the vitamin E group (41.46% vs. 20.46% in the placebo group, P=.04; OR 2.75; 95% CI, 1.05–7.19).
    
    Who: men of infertile couples undergoing IVF at a university hospital; women 18 to 40; 50 vitamin E, 51 placebo
    Effect: live birth per transfer 41.46% vs 20.46% (OR 2.75, 95% CI 1.05 to 7.19, P = .04); per cycle started not significant; sperm parameters no better than placebo
    Certainty: Small; wide CI; per-transfer analysis only, the per-cycle live-birth difference was not significant.
    F&S Reports, 2020 (Matorras et al., vitamin E in men of infertile couples, double-blind randomized study) · checked 2026-10-07 · we read the fulltext
12. ev-vef-12 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of randomized controlled trials · n = 1,227 (live birth, 13 RCTs)
    Due to the very low-quality of the evidence we are uncertain whether antioxidants improve live birth rate compared with placebo or no treatment/standard treatment (odds ratio (OR) 1.81, 95% confidence interval (CI) 1.36 to 2.43; P < 0.001, I2 = 29%; 13 RCTs, 1227 women).
    
    Who: women attending reproductive clinics; oral antioxidants vs placebo or no treatment
    Effect: live birth OR 1.81 (95% CI 1.36 to 2.43), very low quality
    Certainty: 2026 editorial note: 7 included trials since retracted, 2 with expressions of concern; editors judge conclusions unchanged. Vitamin E not analyzed alone in the abstract.
    Cochrane Database Syst Rev, 2020 · checked 2026-10-07 · we read the abstract
13. ev-vef-13 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of randomized controlled trials · n = 3,229
    The evidence suggests that the use of antioxidants makes no difference between the groups in rates of miscarriage (OR 1.13, 95% CI 0.82 to 1.55; P = 0.46, I2 = 0%; 24 RCTs, 3229 women; low-quality evidence).
    
    Who: subfertile women in RCTs of oral antioxidants
    Effect: miscarriage OR 1.13 (95% CI 0.82 to 1.55); multiple pregnancy OR 1.00; GI disturbance OR 1.55 (NS)
    Certainty: Low-quality evidence.
    Cochrane Database Syst Rev, 2020 · checked 2026-10-07 · we read the abstract
14. ev-vef-14 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 40 RCTs
    Conclusions: This review found no high-certainty evidence that dietary supplements improve female infertility outcomes when compared with placebo.
    
    Who: infertile women in RCTs of dietary supplements vs placebo (20 trials) or no treatment (20 trials)
    Effect: vs placebo: no effect on pregnancy-related outcomes, low certainty; vitamin E only hypothesis-generating in secondary analyses
    Certainty: Most trials had some concerns for bias.
    Nutrients, 2026 · checked 2026-10-07 · we read the abstract
15. ev-vef-15 · Position of an expert body · EFSA scientific opinion on the tolerable upper intake level · n = —
    Considering the totality of the available evidence and related uncertainties (Section 3.4 ), the Panel thus retains the UL previously established by the SCF of 300 mg α‐tocopherol/day for adults.
    
    Who: adults in the European Union, including pregnancy and lactation
    Effect: UL 300 mg alpha-tocopherol/day retained; based on bleeding-time studies; US ODS ceiling 1,000 mg/day
    Certainty: 400 mg/day (MOXI, 34223248) exceeds the EFSA UL; 400 IU synthetic is about 180 mg.
    EFSA NDA Panel, Scientific opinion on the tolerable upper intake level for vitamin E, EFSA Journal 2024 (CC BY-ND 4.0) · checked 2026-10-07 · we read the fulltext
16. ev-vef-16 · Position of an expert body · government fact sheet · n = —
    As a result, taking large doses with anticoagulant or antiplatelet medications, such as warfarin (Coumadin), can increase the risk of bleeding, especially in conjunction with low vitamin K intake. The amounts of supplemental vitamin E needed to produce clinically significant effects are unknown but probably exceed 400 IU/day [61].
    
    Who: adults taking anticoagulant or antiplatelet medications
    Effect: bleeding risk with anticoagulants/antiplatelets; clinically significant amounts unknown, probably above 400 IU/day
    Certainty: Fertility trials used 400 IU to 400 mg a day, at or above that threshold.
    NIH Office of Dietary Supplements, Vitamin E Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
17. ev-vef-17 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of RCTs · n = 2504
    Conversely, supplementation with vitamin E was associated with an increased risk of self-reported abdominal pain (RR 1.66, 95% CI 1.16 to 2.37, one trial, 1877 participants) and term prelabour rupture of membranes (PROM) (average RR 1.77, 95% CI 1.37 to 2.28, two trials, 2504 participants, I² = 0%); however, there was no corresponding increased risk for preterm PROM (average RR 1.27, 95% CI 0.93 to 1.75, five trials, 1999 participants, I² = 66%; low quality evidence).
    
    Who: pregnant women in RCTs of vitamin E combined with other supplements
    Effect: term PROM RR 1.77 (95% CI 1.37 to 2.28; 2 trials); abdominal pain RR 1.66 (1.16 to 2.37); preterm PROM RR 1.27 (NS)
    Certainty: Relevant to women who keep taking vitamin E after conceiving; trials mostly vitamin E with vitamin C.
    Cochrane Database Syst Rev, 2015 · checked 2026-10-07 · we read the abstract