What does the research say about CoQ10?
The short answer
In women doing IVF, CoQ10 may improve the chance of a pregnancy being confirmed on a scan. Whether it leads to more babies born hasn't been shown.
What to know
- Most studied in women whose ovaries respond poorly to IVF medication, or who are older.
- The benefit shown sits earlier than a birth: a pregnancy seen on a scan, not a baby home.
- No one has established the best dose, or how long to take it before a cycle.
- Generally well tolerated, but it can interact with blood thinners.
Read the full explanation
If you're considering it
- It's mainly relevant to IVF, particularly if you've been told your egg reserve is low. There's no evidence for it in couples trying naturally.
- The best-known trial used 600 mg a day (200 mg three times a day) for 60 days before IVF, in women under 35 with low reserve.
- Why two to three months: the final stage of an egg's development takes roughly that long, so anything aimed at egg quality needs to start well before a retrieval.
- No study has shown one form (ubiquinol or ubiquinone) works better for fertility.
Be careful
Safety consideration CoQ10 can make warfarin less effective and may affect insulin needs. Its safety in pregnancy hasn't been established, so ask whether to stop once you conceive.
What the evidence is based on
In the trial above (169 women), CoQ10 led to more eggs retrieved and more good-quality embryos, but the difference in live births wasn't statistically clear — the trial was too small to answer that. A Cochrane review of antioxidants for women rated the evidence on live birth as very low. Several studies in that review have since been retracted, though Cochrane says its conclusions stand.
What the research shows
Does CoQ10 supplementation before an IVF cycle improve outcomes?
The research points toward a benefit.
Who was studied. Women undergoing assisted reproduction, several of the trials specifically in poor ovarian responders or women of advanced maternal age.
Outcome measured. Clinical pregnancy
What was found. A meta-analysis of randomized trials found higher clinical pregnancy rates and improved ovarian response measures. Live birth was not established as improved - it was inconsistently reported and underpowered across the trials.
Main limitation. Small, mostly single-centre trials that largely didn't measure live birth.
Why this rating?
Randomized evidence, which is a genuine strength, but the trials are small, several are single-centre, populations differ, and the outcome most people care about was not the outcome most reliably measured. That is the classic pattern for a low-certainty benefit signal.
Questions for your doctor
Edit any of these before you add it — they're yours. Your list stays in this browser, and you can print a one-page sheet from it.
- Given my ovarian reserve, is CoQ10 worth trying before my next cycle?
- Does it interact with anything I'm taking, including blood thinners?
- What dose, and for how long before retrieval?
Sources
- Xu et al., CoQ10 before IVF in women with low ovarian reserve: randomized trial, Reproductive Biology and Endocrinology 2018
- Florou et al., CoQ10 in ART: systematic review and meta-analysis of RCTs, J Assist Reprod Genet 2020
- Cochrane Review, Antioxidants for female subfertility (2020)
- NIH National Center for Complementary and Integrative Health, Coenzyme Q10