Walk into any health food store or open any fertility forum and you'll encounter dozens of supplements marketed to people trying to conceive. Some have solid research behind them. Many do not. A few may actively interfere with treatment. This guide provides an honest, research-graded assessment of the most commonly used fertility supplements — separately for women and men — so you can make informed decisions with your doctor.
How to Read Supplement Research
Before diving into individual compounds, it helps to understand how to evaluate supplement studies:
Randomized Controlled Trials (RCTs) are the gold standard. They compare a supplement to a placebo, randomly assigning participants. These provide the strongest evidence of causation.
Observational studies show correlations — people with higher levels of a nutrient tend to have better outcomes — but can't prove cause and effect. Low vitamin D levels may be correlated with poor IVF outcomes because deficiency is a marker of generally poor health, not because vitamin D directly drives IVF success.
Surrogate endpoints (like sperm count, follicle count, or hormone levels) are easier to measure than actual pregnancy rates and live births. Many supplement studies show improvements in surrogate markers without demonstrating improvements in what actually matters: pregnancy and live birth rates.
Evidence ratings used in this guide:
- Strong: Multiple high-quality RCTs with consistent results, or a favorable Cochrane systematic review
- Moderate: Some RCT data but studies are small, inconsistent, or primarily observational
- Weak: Mainly observational data, animal studies, or theoretical mechanism only
- Insufficient/Conflicting: Evidence exists but contradicts itself or quality is too poor to draw conclusions
FDA Supplement Regulation Limitations
The FDA does not approve dietary supplements for safety or efficacy before they reach the market. Manufacturers are responsible for ensuring their products are safe, but third-party verification is voluntary. When choosing supplements:
- Look for third-party testing seals (USP Verified, NSF International, ConsumerLab)
- Be skeptical of dramatic marketing claims
- Higher price does not necessarily mean higher quality
- Always check with your reproductive endocrinologist before starting any supplement during an IVF cycle
Women's Fertility Supplements
Folate / Methylfolate
Evidence: Strong
Folate is the most evidence-backed supplement in reproductive medicine, with decades of data. The NIH recommends 400-800 mcg daily starting at least one month before conception. The primary benefit is prevention of neural tube defects (NTDs) — the evidence for this is definitive. Emerging data also suggests adequate folate supports oocyte quality and reduces miscarriage risk related to chromosomal abnormalities.
Key consideration: Women with the MTHFR C677T variant (which affects folate metabolism) should consider 5-MTHF (methylfolate) rather than standard folic acid, as they may not efficiently convert the synthetic form.
Typical dose: 400-800 mcg folic acid daily, or 400-1,000 mcg 5-MTHF for MTHFR variant carriers.
CoQ10 (Ubiquinol)
Evidence: Moderate
CoQ10 is a mitochondrial energy compound found in high concentrations in developing eggs. Mitochondrial function is critical for egg quality and embryo development. A 2018 meta-analysis by Xu et al. published in the Journal of Assisted Reproduction and Genetics found CoQ10 supplementation was associated with significantly higher clinical pregnancy rates in IVF patients, particularly in women with poor ovarian response and diminished ovarian reserve.
The ASRM notes that while CoQ10 shows promise, the evidence is not yet sufficient to make a universal recommendation. Ubiquinol form is better absorbed than ubiquinone.
Typical dose: 200-600 mg/day (ubiquinol form preferred). Start 2-3 months before IVF to allow time for cellular accumulation.
Important note: Discontinue CoQ10 before egg retrieval if your clinic advises it — high-dose antioxidants around retrieval are a point of controversy (discussed below).
DHEA (Dehydroepiandrosterone)
Evidence: Moderate
DHEA is an androgen precursor produced by the adrenal glands. Supplementation before IVF has been studied specifically in women with diminished ovarian reserve (DOR) and poor ovarian response. Several small RCTs and the work of Gleicher and Barad suggest DHEA supplementation for 8-12 weeks before IVF improves ovarian response, egg yield, and pregnancy rates in poor responders.
However, not all studies agree, and DHEA is not appropriate for all patients. Women with PCOS (who typically have elevated androgens already) should not take DHEA. It is a controlled substance in some countries and should only be used under physician supervision.
Typical dose: 25-75 mg/day for 6-12 weeks before IVF. Requires physician supervision.
Vitamin D
Evidence: Moderate
Vitamin D receptors are present in ovarian follicles, endometrial tissue, and reproductive immune cells. Multiple large observational studies link vitamin D sufficiency (levels >30 ng/mL, ideally 40-60 ng/mL) to better IVF outcomes, including higher implantation and live birth rates.
A 2019 RCT in the Lancet found vitamin D supplementation in deficient women undergoing IVF improved live birth rates compared to placebo. This is among the strongest single-supplement IVF evidence available.
Get your 25-OH vitamin D level tested. If deficient (<20 ng/mL), supplementation is clearly warranted. If insufficient (20-30 ng/mL), supplementation is reasonable.
Typical dose: 1,000-4,000 IU/day depending on baseline levels. Check levels 8-12 weeks after starting supplementation.
Omega-3 Fatty Acids (DHA/EPA)
Evidence: Moderate
Omega-3s are structural components of oocyte cell membranes and are present in high concentrations in follicular fluid. DHA specifically is critical for fetal brain development in early pregnancy. Observational studies consistently link higher omega-3 intake and blood levels to better IVF embryo quality and implantation rates.
A high-quality prenatal vitamin will typically contain some DHA, but for those not eating fatty fish 2-3 times per week, an additional omega-3 supplement is reasonable.
Typical dose: 1,000-2,000 mg combined EPA+DHA daily.
Melatonin
Evidence: Moderate (IVF-specific)
Melatonin is best known as a sleep hormone, but it is also a potent antioxidant concentrated in follicular fluid. Its fertility relevance is primarily in the IVF context: several small RCTs have shown that melatonin supplementation during ovarian stimulation increases follicular fluid melatonin levels and may improve egg quality in poor responders.
The evidence does not support melatonin for general fertility in normally cycling women. It should not be taken continuously as it can affect the circadian rhythm.
Typical dose: 3 mg at bedtime during ovarian stimulation only, with physician approval.
Inositol (Myo-Inositol and D-Chiro-Inositol)
Evidence: Strong for PCOS
Inositol is the fertility supplement with the strongest evidence base for women with PCOS. Myo-inositol is an insulin-sensitizing compound that mimics the action of insulin in ovarian tissue. Multiple RCTs have shown myo-inositol supplementation improves menstrual regularity, reduces androgen levels, and improves egg quality in women with PCOS undergoing IVF.
The ASRM notes inositol as a reasonable adjunct for PCOS management. It is generally well-tolerated and inexpensive.
Typical dose: 2-4 g myo-inositol per day (often combined with 200-400 mcg folate). The 40:1 ratio of myo-inositol to D-chiro-inositol mimics physiological ratios.
N-Acetyl Cysteine (NAC)
Evidence: Moderate for PCOS; Weak for general fertility
NAC is a precursor to glutathione, the body's master antioxidant. Studies in PCOS patients show NAC improves insulin sensitivity and may improve ovulation rates. A small number of RCTs have also investigated NAC during IVF with mixed results.
For general fertility enhancement, evidence is insufficient. For PCOS, it is a reasonable adjunct at low cost.
Typical dose: 1,200-1,800 mg/day in divided doses.
Taking Charge of Your Fertility Journey
Understanding which supplements are worth taking is part of optimizing your path to conception.
Before or alongside clinical treatment, many people explore at-home insemination. MakeAMom makes reusable at-home insemination kits — the CryoBaby for frozen or low-volume sperm, the Impregnator for low-motility sperm, and the BabyMaker for those with sensitivities — all designed for home use without a clinic visit.
Explore home insemination kits at MakeAMom →
Men's Fertility Supplements
Zinc
Evidence: Strong
Zinc is the most important mineral for male reproductive function. It is highly concentrated in seminal fluid and sperm, and is required for testosterone synthesis, sperm production, and sperm motility. Multiple studies link zinc deficiency to reduced sperm count, motility, and morphology.
A Cochrane review of antioxidants for male infertility (Showell et al.) found zinc supplementation significantly improved sperm parameters, with evidence for improved live birth rates in some analyses.
Typical dose: 25-50 mg elemental zinc daily (zinc gluconate or zinc citrate forms preferred).
Selenium
Evidence: Moderate
Selenium is an antioxidant mineral that protects sperm from oxidative DNA damage. Low selenium status is associated with impaired sperm motility. Combined selenium + vitamin E supplementation has been shown in some RCTs to improve sperm motility and morphology. The Cochrane antioxidant meta-analysis found selenium among the more promising male fertility supplements.
Typical dose: 100-200 mcg/day (note: Brazil nuts provide approximately 70-90 mcg per nut).
CoQ10
Evidence: Moderate
The Cochrane review on antioxidants for male subfertility found CoQ10 significantly improved sperm concentration and motility compared to placebo. A 2013 meta-analysis by Lafuente et al. confirmed improvements in sperm parameters. However, direct evidence of improved live birth rates remains limited.
Typical dose: 200-400 mg/day (ubiquinol form preferred).
Omega-3 Fatty Acids
Evidence: Moderate
DHA is a major structural component of sperm cell membranes, concentrated in the sperm tail. Low DHA levels are associated with impaired sperm motility. Supplementation studies show improvements in sperm motility and morphology, particularly in men with low baseline DHA.
Typical dose: 1,000-2,000 mg combined EPA+DHA daily.
Folate
Evidence: Moderate
Folate is required for DNA synthesis and repair in sperm production. Deficiency is associated with increased sperm DNA fragmentation and aneuploidy (chromosomal abnormalities in sperm). A small number of RCTs show folate supplementation reduces sperm DNA fragmentation.
Typical dose: 400-800 mcg daily.
Vitamin D
Evidence: Moderate
Vitamin D receptors are present in sperm cells, and vitamin D influences testosterone synthesis and sperm motility. Deficient men show lower testosterone levels and poorer sperm parameters. Supplementation in deficient men has been shown to improve testosterone and motility in some RCTs.
Typical dose: Same as for women — test first, supplement to achieve 40-60 ng/mL.
Lycopene
Evidence: Weak to Moderate
Lycopene is an antioxidant carotenoid found in tomatoes, watermelon, and pink grapefruit. Animal studies and small human trials suggest lycopene may improve sperm concentration and morphology, potentially by reducing oxidative damage to sperm DNA. The evidence is preliminary but promising enough that it appears in some male fertility supplement formulas.
Typical dose: 4-8 mg/day (easily achieved through diet — one tablespoon of tomato paste provides approximately 15 mg).
Evidence Summary Table
Women's Supplements
| Supplement | Evidence Level | Best For | Notes |
|---|---|---|---|
| Folate/Methylfolate | Strong | All women TTC | Start 1 month before conception |
| CoQ10 (Ubiquinol) | Moderate | DOR, advanced age | Start 2-3 months before IVF |
| DHEA | Moderate | Poor ovarian response | Physician supervision required |
| Vitamin D | Moderate | Deficient women | Test before supplementing |
| Omega-3 (DHA/EPA) | Moderate | All women TTC | Especially if low fish intake |
| Melatonin | Moderate | IVF poor responders | Short-term use only |
| Myo-Inositol | Strong | PCOS | Well-studied in PCOS specifically |
| NAC | Moderate (PCOS) | PCOS | Reasonable adjunct |
Men's Supplements
| Supplement | Evidence Level | Best For | Notes |
|---|---|---|---|
| Zinc | Strong | All men with sperm issues | Cochrane support |
| Selenium | Moderate | Low motility | Often combined with vitamin E |
| CoQ10 | Moderate | Low motility/concentration | Cochrane support |
| Omega-3 (DHA) | Moderate | Low motility | Critical for sperm membrane |
| Folate | Moderate | High sperm DNA fragmentation | DNA integrity support |
| Vitamin D | Moderate | Deficient men | Test first |
| Lycopene | Weak-Moderate | Morphology | Achievable through diet |
For more on treating male factor infertility, see our male infertility causes and treatment guide.
The Antioxidant Paradox: What NOT to Take During IVF
This is a critically important and often overlooked issue. While antioxidants are broadly beneficial before and between IVF cycles, there is legitimate concern that high-dose antioxidant supplementation during active IVF stimulation — specifically around egg retrieval and fertilization — may interfere with embryo development.
Reactive oxygen species (ROS) are often thought of as purely harmful, but in reproductive biology they serve essential signaling functions. Fertilization itself involves a controlled oxidative burst. Some laboratory data suggests that very high levels of exogenous antioxidants can disrupt these signals.
A 2019 analysis raised concerns specifically about high-dose vitamin C and E supplementation during IVF. No definitive human RCT has proven harm, but the mechanism is plausible enough that many reproductive endocrinologists advise pausing high-dose antioxidants (CoQ10 >600mg, vitamin C >500mg, vitamin E >400 IU) around retrieval and transfer.
General guidance:
- Continue standard prenatal vitamins throughout IVF
- Discuss any additional supplements with your RE before your stimulation cycle begins
- When in doubt, pause extra supplements around retrieval and transfer
- Resume after transfer under physician guidance
When to Start Supplements
The timeline matters enormously:
| Supplement | When to Start |
|---|---|
| Folate | At least 1 month before TTC; ideally 3 months |
| CoQ10 | 2-3 months before IVF egg retrieval |
| DHEA | 6-12 weeks before IVF (physician supervised) |
| Vitamin D | As soon as deficiency identified |
| Omega-3 | 2-3 months before attempting conception |
| Inositol (PCOS) | 3+ months before IVF |
| Zinc/Selenium (men) | 3 months before (sperm maturation cycle) |
Sperm takes approximately 74 days to mature. For male supplements to affect the sperm being ejaculated today, treatment needs to have begun approximately 2.5 months ago. This means men should start fertility supplements at least 3 months before planned insemination or IVF with ICSI.
The Bottom Line
A few fertility supplements have genuinely good evidence — folate and methylfolate for all women, myo-inositol for PCOS, zinc for male sperm parameters, vitamin D for those who are deficient. These are worth discussing with your doctor regardless of treatment path.
Many other supplements have promising but limited data. CoQ10, omega-3, and selenium are reasonably supported and low-risk, making them worth considering in consultation with your reproductive endocrinologist.
Be skeptical of "complete fertility blend" products with proprietary formulas, dramatic marketing claims, and prices that suggest you're paying for a brand rather than research. The individual ingredients matter; the packaging does not.
For PCOS-specific supplement protocols, see our PCOS fertility guide.
Frequently Asked Questions
Q: Which fertility supplements have the strongest evidence? A: For women, folate/methylfolate has decades of strong RCT evidence — the NIH recommends 400–800 mcg daily starting at least one month before conception, primarily for neural tube defect prevention but also supporting oocyte quality. Myo-inositol has strong evidence specifically for women with PCOS. For men, zinc has Cochrane-supported evidence showing improvements in sperm parameters and some analyses showing improved live birth rates.
Q: Should I take CoQ10 before IVF? A: CoQ10 (ubiquinol form, 200–600 mg/day) shows moderate evidence for IVF patients — a 2018 meta-analysis found associated improvements in clinical pregnancy rates, particularly in women with poor ovarian response and diminished ovarian reserve. ASRM notes the evidence is not sufficient for a universal recommendation, but the risk profile is low. Start 2–3 months before IVF to allow cellular accumulation, and discontinue around egg retrieval if your clinic advises it.
Q: Is DHEA safe to take without a doctor's supervision? A: No — DHEA should only be used under physician supervision. It is an androgen precursor that is not appropriate for all patients (women with PCOS who already have elevated androgens should not take it), is a controlled substance in some countries, and should be used for a specific duration (6–12 weeks before IVF) in patients with diminished ovarian reserve or poor ovarian response. Self-prescribing DHEA without guidance is not recommended.
Q: Should I stop supplements during an IVF cycle? A: High-dose antioxidants (CoQ10 above 600 mg, vitamin C above 500 mg, vitamin E above 400 IU) may interfere with the reactive oxygen species signaling involved in fertilization. Many reproductive endocrinologists advise pausing these supplements around egg retrieval and transfer. Standard prenatal vitamins should be continued throughout. Always discuss any supplements you are taking with your RE before your stimulation cycle begins.
Q: How early before trying to conceive should men start fertility supplements? A: Sperm takes approximately 74 days to mature — meaning supplements started today won't affect the sperm being ejaculated for approximately 2.5 months. Men should start fertility supplements (zinc, CoQ10, omega-3, selenium) at least 3 months before planned insemination or IVF with ICSI to allow sufficient time for improvements in sperm parameters.
