What does CoQ10 do for women? What the research does and doesn't show

The evidence doesn't support CoQ10 as a general supplement for women's health. The trials in women studied PCOS and fertility treatment, with mixed results: more clinical pregnancies in one pooled analysis, no significant difference in live births, and no doses in the abstracts. None tested estrogen levels.

What the evidence doesn't support

It doesn't support CoQ10 as a treatment for infertility or PCOS, or as a way to change estrogen: none of the abstracts we read measured estradiol. It doesn't show a better chance of a baby, because the one analysis that counted live births found no significant difference. It doesn't give a dose for women: the abstracts below state none, and nothing we read compares women with men. And it doesn't tell us anything about use in pregnancy or breastfeeding. We give no use guidance for either; our sources reported conception outcomes, not safety during pregnancy.

What the trials found

Women having fertility treatment, 5 trials. A 2020 meta-analysis of five randomised trials (449 women with infertility undergoing assisted reproduction; 215 on CoQ10, 234 on placebo or no treatment) found clinical pregnancy in 28.8% versus 14.1% (odds ratio 2.44, 95% CI 1.30 to 4.59). Live births did not differ significantly (odds ratio 1.67, 95% CI 0.66 to 4.25) and neither did miscarriage (0.61, 95% CI 0.13 to 2.81). The abstract gives no dose or duration (Florou 2020).

PCOS, 9 trials. A 2023 meta-analysis of nine randomised trials in 1,021 women with polycystic ovary syndrome reported HOMA-IR (an insulin resistance score), fasting glucose and testosterone as lower (testosterone SMD -0.28, 95% CI -0.49 to -0.06), and FSH as higher. Only one trial reported adverse events, and it found none. The abstract states no dose and doesn't say which trials fed each outcome (Zhang 2023).

The wider field, a Cochrane review. A 2020 review of 63 trials in 7,760 women attending fertility clinics grouped CoQ10 with a dozen other antioxidants and didn't separate it out. It rated the evidence low to very low quality, was uncertain whether antioxidants improve live birth, and found no difference in miscarriage or gastrointestinal problems. A 2026 editorial note says seven of the included studies have since been retracted and two carry expressions of concern; the editors judged the conclusions unchanged (Showell 2020).

Fatigue ratings, mixed groups. A 2022 meta-analysis of 13 trials (1,126 healthy and diseased people) found lower fatigue scores with CoQ10. It was not a trial in women, and doses and forms were pooled (Tsai 2022). See CoQ10 benefits: what the research does and doesn't show.

Questions people ask

How much CoQ10 per day for a woman, and how much should a woman take?

There is no established dose, for women or anyone, and this page doesn't recommend one. The fertility and PCOS abstracts above state no dose. For the doses used in the studies we read across outcomes, see CoQ10 dosage; for 200, 400, 500 or 600 mg specifically, no trial we read in women tested them against placebo.

How much CoQ10 for female fertility, and does it help fertility?

The trials we read were in women already having fertility treatment, and they reported more clinical pregnancies but no significant live-birth difference. A woman trying to conceive should see a clinician; a supplement is not a fertility treatment, and we give no dose for it.

Does CoQ10 increase estrogen?

We found no trial in our sources that tested it. The PCOS analysis reported FSH and testosterone, not estrogen.

What does CoQ10 do for the female body, and what is it used for in women?

In the body it is a component of cells' energy machinery in both sexes, with no female-specific role in the sources we read. In research in women, it has been tested in PCOS and fertility treatment, above.

Is CoQ10 good for women, or for a woman of 80?

The studied outcomes are above, in specific groups. We found no trial specific to older women. Whether a supplement is right depends on your health and medicines; ask a clinician.

What are the side effects of CoQ10 for women, and can women take it?

The sources we read reported no side effects specific to women. Stomach complaints are the commonly reported ones; see CoQ10 side effects and who should not take CoQ10. If you are pregnant or breastfeeding, ask your doctor before taking any supplement.

When to talk to a doctor

If you have been trying to conceive for a year, or have irregular periods, a doctor can look for causes and treatments with evidence behind them. CoQ10 is not a treatment for PCOS or infertility. If you are pregnant, breastfeeding or take prescription medicine, especially a blood thinner, ask your doctor or pharmacist before adding any supplement.

Related reading: CoQ10, diabetes and PCOS, CoQ10 side effects, CoQ10 dosage.