The Best Natural Fertility Supplements for Women (Backed by Science)

I know that trying to conceive can feel overwhelming, especially with the sheer number of supplements on the shelf claiming to boost fertility. If you’re reading this, you’re probably one of many women wondering which ones are actually worth your investment. While not all fertility supplements are created equal, there are a handful that stand out with stronger scientific support. These supplements can improve egg quality, help balance hormones, support implantation, and increase your chances of conception.

Let’s break down the best natural fertility supplements that are actually backed by research, talk about typical effective doses, and add a Traditional Chinese Medicine (TCM) perspective to connect modern science with time‑honored wisdom. Having worked with many women, this topic has kept me up many nights. I’ve done the research so you don’t have to. Here we go:

1. Coenzyme Q10 (CoQ10)

• Science: CoQ10 powers mitochondria, the energy engines inside cells. Eggs are highly energy‑demanding, and mitochondrial health directly impacts egg quality.

  • A 2018 randomized controlled trial (RCT) found that women with poor ovarian reserve who took 600 mg/day of CoQ10 for 60 days before IVF‑ICSI had significantly higher numbers of retrieved oocytes, improved fertilization rates, and more high‑quality embryos compared to controls (Xu et al., 2018)

  • A 2020 systematic review and meta‑analysis of five RCTs (449 women undergoing medical fertility treatments) showed that CoQ10 nearly doubled clinical pregnancy rates compared to placebo or no treatment (28.8% vs. 14.1%). The analysis also found a trend toward higher live birth rates and lower miscarriage rates with CoQ10, though these were not statistically significant likely due to the small number of studies available (Florou et al., 2020).

• Typical dose:

  • 600 mg/day for 2 months before IVF‑ICSI

  • Meta-analyses support this higher dosing for improved outcomes; some clinicians use 200–400 mg/day for a minimum of 8–12 weeks off-label for fertility support. The ubiquinol form has better absorption.

• TCM perspective: Strengthens Kidney Qi and Essence (Jing), nourishing the foundation of reproductive vitality.

💡 For a deeper dive into foods that naturally support egg quality alongside supplements, see my post: What to Eat for Egg Quality: A Holistic Fertility Nutrition Guide.

2. Myo‑Inositol (± D‑Chiro‑Inositol)

• Science: Myo‑inositol is a naturally occurring compound involved in insulin signaling and ovarian function. It has been especially studied in women with PCOS, where it improves ovulation, egg quality, and metabolic balance.

  • A 2021 meta‑analysis found that women with PCOS undergoing IVF/ICSI who took 4 g/day of myo‑inositol for about 3 months had consistent improvements in oocyte maturation and embryo quality. However, the review noted no significant evidence yet for higher clinical pregnancy or live birth rates, and called for larger RCTs to confirm these outcomes (Merviel et al., 2021).

  • Individual RCTs have shown promising results for restoring ovulation and improving pregnancy rates in PCOS, but the strongest evidence at this time is for egg and embryo quality improvements.

• Typical dose: 4 g/day (2 g twice daily), often combined with D‑chiro‑inositol in a 40:1 ratio to reflect physiological ovarian levels.

• TCM perspective: In Traditional Chinese Medicine, PCOS often corresponds to phlegm‑damp accumulation and disharmony of the Shen (mind/spirit). By improving insulin sensitivity and cycle regularity, Myo‑inositol helps “clear dampness” and harmonize cycles.

✨ Not sure if you’re ovulating regularly? Here’s how to recognize the signs naturally: How to Know If You’re Ovulating (Without Expensive Tests).

3. Omega‑3 Fatty Acids (EPA/DHA)

• Science: Omega‑3 fats help reduce inflammation, support hormone balance, improve uterine lining, and may enhance embryo implantation.

  • A prospective cohort (n ≈ 900) found omega‑3 supplement users had a 1.5× higher likelihood of spontaneous conception each cycle (adjusted for age, BMI, and prenatal vitamin use). (Stanhiser et al., 2022)

  • In women undergoing IVF/ICSI, higher blood levels of EPA + DHA were significantly associated with live birth outcomes. Live birth probability increased by ~8% for each percentage point increase in serum omega‑3 (adjusted RR = 2.37; 95% CI 1.02–5.51). (Chiu et al., 2018)

• Typical dose: ~1 g combined EPA/DHA per day from fish oil, algae oil, or dietary sources (e.g., two servings of low-mercury oily fish per week). Exact supplement doses varied across cohort participants.

• TCM perspective: Considered to nourish Blood and Yin, balance internal “heat,” and strengthen uterine lining and implantation capacity.

4. Vitamin D

• Science & Evidence:
  Vitamin D plays an essential role in reproductive health, affecting ovarian function, immune modulation, and endometrial receptivity. Deficiency is common in women of reproductive age and has been linked to poorer IVF outcomes.

  • A large Hong Kong cohort study of over 1,100 women found that those with sufficient vitamin D levels (≥50 nmol/L) before ovarian stimulation had a significantly higher cumulative live birth rate compared to deficient women (≈50.9% vs. 43.9%, p = 0.021), even after adjusting for age, BMI, and ovarian reserve (Li et al., 2022).

  • A 2022 meta‑analysis of randomized controlled trials found that vitamin D supplementation increased chemical pregnancy rates (RR ≈ 1.53; 95% CI 1.06–2.20), but did not significantly improve clinical pregnancy or live birth rates (Zhou et al., 2022).

  • In women with PCOS, a 2023 meta‑analysis found vitamin D supplementation was associated with improved ovulation and pregnancy rates, and reduced miscarriage risk, though the quality of evidence was low to moderate (Yang et al., 2023).

• Typical dose: 1,000–2,000 IU/day is commonly recommended for women trying to conceive. Higher doses (up to 4,000 IU/day) may be prescribed short‑term in cases of deficiency, ideally guided by blood testing (25‑hydroxyvitamin D levels).

• TCM perspective: In Traditional Chinese Medicine, vitamin D corresponds to supporting Yang and nourishing Essence. By strengthening warmth, bone health, and immune balance, it helps create the optimal conditions for conception.

5. N‑Acetylcysteine (NAC)

• Science: NAC boosts glutathione, the body’s master antioxidant, and supports ovulation.

  • A recent systematic review & meta-analysis of 22 studies involving 2,515 women with PCOS found that NAC significantly improved progesterone levels, endometrial thickness, and LH—the key markers linked to ovulation and uterine receptivity. Yet, the analysis did not include data on clinical pregnancy or live birth outcomes, indicating more research is still needed to clarify NAC’s impact on fertility (Viña & Carranza, 2025).

  • NAC combined with clomiphene enhanced ovulation and pregnancy outcomes compared to meds alone. (Hassan et al., 2018)

  • A recent prospective cohort study in women with endometriosis showed that NAC (600 mg, three times daily, three days per week for three months) significantly reduced pelvic pain, endometrioma size, and CA‑125 levels. Among women desiring pregnancy, 75% conceived within six months of starting NAC, suggesting a potential fertility benefit in this specific population (Anastasi et al., 2023).

• Typical dose: 1,200–1,800 mg/day

• TCM perspective: Resolves phlegm‑damp, clears oxidative “heat,” and promotes regular cycles.

6. Methylated Prenatal Folate (L‑5‑MTHF)

• Science: Folate supports DNA methylation and neural tube development. 5‑MTHF is better absorbed than synthetic folic acid, especially in women with MTHFR variants.

  • A randomized trial (FASSTT) found that women who took 400 µg/day of folic acid in the second and third trimesters (after the neural tube closure window) gave birth to infants with measured epigenetic changes (at genes like ZFP57, IGF2, and BDNF) in cord blood, confirming that prenatal folate may influence long-lasting gene expression patterns (Irwin et al., 2019; Ondičová et al., 2022).

• Typical dose: 400 µg/day; up to 4 mg/day if high risk (e.g., history of neural tube defect). Today, many practitioners recommend methylated folate (L‑5‑MTHF) instead of folic acid. Unlike folic acid, 5‑MTHF is the active form, which means it can be used directly by the body. This is especially important for women with MTHFR genetic variants, who may not process folic acid efficiently.

• TCM perspective: Nourishes Blood and Essence, supporting implantation and fetal growth.

7. Antioxidants (Vitamins C & E)

• Science & Evidence:
  Vitamins C and E are classic antioxidants that help protect eggs and embryos from oxidative stress.

  • A 2020 Cochrane review of randomized trials found very low‑certainty evidence that antioxidant supplements, including vitamins C and E, improve fertility outcomes. They did not consistently increase clinical pregnancy or live birth rates (Showell et al., 2020).

  • An observational study of 437 women in fertility treatment found that higher vitamin C intake was linked to a shorter time to pregnancy, especially in younger women with healthy BMI. Vitamin E showed weaker, less consistent associations. Importantly, neither vitamin C nor E intake was linked to higher live birth rates (Ruder et al., 2014).

• Typical dose (as studied):

  • Vitamin C: 500–1,000 mg/day

  • Vitamin E: 400–600 IU/day

• TCM perspective:
  In Traditional Chinese Medicine, antioxidants like vitamin C and E are seen as clearing heat and protecting Yin, helping safeguard reproductive Essence from oxidative damage.

8. Alpha Lipoic Acid

• Science & Evidence:
  ALA is a strong antioxidant that also improves mitochondrial energy and insulin sensitivity. ALA looks promising for improving egg and embryo quality in IVF and PCOS, with animal data supporting its protective effects on eggs, but more large human trials are needed to confirm fertility and live birth outcomes.

  • In a 2020 pilot trial of overweight women undergoing IVF, ALA (800 mg/day) with myo‑inositol and folate improved egg and embryo quality over folate alone, and pregnancies and live births occurred only in the fomer group (Canosa et al., 2020).

  • A 2021 systematic review of both male and female infertility trials concluded that ALA shows positive effects on ovarian maturation, embryo development, menstrual regulation, and sperm quality, while highlighting the need for more robust clinical trials (Di Tucci et al., 2021).

  • In animal studies, ALA protected eggs from oxidative DNA damage and preserved egg quality under stress (Wang et al., 2023).

• Typical dose (as studied): 600–800 mg/day, often combined with other nutrients.

• TCM perspective: In TCM, ALA’s antioxidant role corresponds to clearing heat and nourishing Yin, protecting reproductive Essence.

9. Probiotics & Fertility Microbiome Support

• A Lactobacillus‑dominant vaginal and endometrial microbiome is strongly linked to better fertility outcomes, especially in IVF settings.

  • In a 2016 IVF study, women with a Lactobacillus‑dominant endometrium had higher implantation (60.7% vs. 23.1%) and live birth (58.8% vs. 6.7%) rates compared to those with non‑Lactobacillus‑dominant microbiota (Moreno et al., 2016).

  • A 2023 randomized controlled trial of women undergoing frozen embryo transfer found that short‑term vaginal Lactobacillus supplementation did not increase overall pregnancy rates, but it reduced miscarriage risk (9.5% vs. 19.1%) and improved live birth rates in blastocyst transfers (35.7% vs. 22.2%) (Thanaboonyawat et al., 2023).

  • Natural fertility: To date, no quality studies have tested probiotics in women trying to conceive naturally. Current evidence is IVF‑specific.

• Typical dose: ≥10⁹–10¹⁰ CFU/day multi‑strain probiotic (esp. Lactobacillus crispatus, L. rhamnosus); fermented foods add additional benefit.

• TCM perspective: Strengthens Spleen Qi, supports digestion and nutrient absorption, and harmonizes cycles.

FAQs About Fertility Supplements

What is the best supplement to improve egg quality?
CoQ10 has the most consistent evidence for improving egg quality. Antioxidants like vitamin C, vitamin E, and alpha‑lipoic acid may also help protect eggs from oxidative stress, though their effects on pregnancy and live birth outcomes are less clear.

Do I need to take all of these supplements?
Not necessarily. The best approach is personalized, depending on your health history, lab results, and fertility challenges.

How long should I take fertility supplements before trying to conceive?
Most studies suggest at least 3–4 months of consistent use, since this matches the egg maturation cycle.

Can supplements replace fertility treatments?
No. Supplements can support natural conception and may improve outcomes with fertility treatments, but they work best as part of a comprehensive fertility plan that may also include lifestyle medicine, acupuncture, or medical care.

Are these supplements safe to take during IVF?
Most of the supplements discussed including CoQ10, folate, vitamin D, NAC, and probiotics, have been studied in IVF settings and shown to be safe. Some, like CoQ10 and NAC, may even improve outcomes. That said, always review supplements with your fertility specialist to ensure they fit with your treatment protocol.

Do men also benefit from fertility supplements?
Yes. Male fertility is equally affected by oxidative stress. Supplements such as CoQ10, vitamin C, vitamin E, alpha‑lipoic acid, and omega‑3 fatty acids have been shown to improve sperm motility and morphology. While not all studies show higher pregnancy rates, they do support healthier sperm and may improve chances of conception when taken consistently.

What about L‑carnitine?
L‑carnitine has stronger evidence in male fertility, where it improves sperm quality and may increase pregnancy rates. In women, the research is still very limited to small studies and animal data, so it hasn’t yet reached the level of evidence seen with supplements like CoQ10, NAC, or vitamin D. That being said, it may be useful in the certain situations depending on your health and history.

Final Words

The supplement aisle may be crowded, but science tells us a clearer story: only a few key supplements have been shown to consistently support fertility and reproductive health. The strongest evidence comes from studies in women undergoing assisted reproductive technologies (IVF, ICSI, frozen embryo transfer), where supplements like CoQ10, vitamin D, NAC, omega‑3s, and probiotics have been shown to improve egg and embryo quality, implantation, or pregnancy outcomes.

For women trying to conceive naturally, the data is more limited. Some supplements, such as CoQ10 and NAC in women with PCOS, show benefits in ovulation and pregnancy rates when combined with fertility medications. For others, the evidence comes mostly from mechanistic studies, small trials, or observational data.

That said, supplements are not magic bullets. The most powerful results come when they’re combined with whole‑food nutrition, acupuncture, stress support, and a holistic lifestyle.

If you’re preparing for IVF, don’t miss my week‑by‑week holistic IVF guide to support your cycle alongside medical care. And if you’re curious about the bigger picture of health see my post on how to eat for hormone health.

References

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2. Florou, P., Anagnostis, P., Theocharis, P., Chourdakis, M., & Goulis, D. G. (2020). Does coenzyme Q₁₀ supplementation improve fertility outcomes in women undergoing assisted reproductive technology procedures? A systematic review and meta-analysis of randomized‑controlled trials. Journal of Assisted Reproduction and Genetics, 37(10), 2377–2387. https://doi.org/10.1007/s10815-020-01906-3

3. Merviel, P., James, P., Bouée, S., Le Guillou, M., Rince, C., Nachtergaele, C., & Kerlan, V. (2021). Impact of myo‑inositol treatment in women with polycystic ovary syndrome in assisted reproductive technologies. Reproductive Health, 18, 13. https://doi.org/10.1186/s12978-021-01073-3

4. Stanhiser, J., Steiner, A. Z., Hauser, R., Wise, L. A., & Time‑to‑Conceive Collaboration. (2022). Omega‑3 fatty acid supplementation and fecundability: A prospective cohort analysis. Human Reproduction, 37(5), 1139–1147. https://doi.org/10.1093/humrep/deac027

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