Best supplements when you're trying to get pregnant
The fertility supplement market is enormous, and most of what's on the shelf is either unproven or priced far above what the evidence justifies. A prenatal vitamin is non-negotiable. Beyond that, the list of supplements with real research behind them is shorter than you'd think. Here's what's worth considering, what's overhyped, and how to avoid spending $200 a month on pills that don't do anything.
The non-negotiable: prenatal vitamin with folic acid
Start this before you're pregnant. The CDC recommends that all women of reproductive age who could become pregnant take 400 mcg of folic acid daily. This is the single most evidence-backed recommendation in preconception care. Folic acid reduces the risk of neural tube defects (serious birth defects of the brain and spine) by 70% or more. The neural tube closes by week 4 of pregnancy, often before a woman knows she's pregnant. If your folate levels aren't adequate at that point, the window has closed.
Any over-the-counter prenatal vitamin with at least 400 mcg of folic acid works. Brand doesn't matter. methylfolate (the active form) vs folic acid (the synthetic form) is a debate that comes up often: women with the MTHFR gene variant (roughly 30 to 40% of the population) may absorb methylfolate better. If you know you have this variant, methylfolate is worth the switch. If you don't know, folic acid is fine for most women.
CoQ10: the supplement with the most promising fertility evidence
Coenzyme Q10 is an antioxidant that plays a role in mitochondrial energy production. Eggs have more mitochondria than almost any other cell in the body, and mitochondrial function declines with age. The theory, supported by a growing body of research, is that CoQ10 supplementation improves egg quality by giving the mitochondria more of the fuel they need.
A 2018 study published in the Journal of Ovarian Research found that women who took 600 mg of CoQ10 daily for 60 days before IVF had significantly higher ovarian response and better embryo quality compared to a control group. A 2023 meta-analysis in Reproductive Biology and Endocrinology concluded that CoQ10 supplementation improved pregnancy rates in women undergoing fertility treatment, with the strongest effects in women over 35.
CoQ10 is fat-soluble, so take it with a meal that contains fat. The dose used in most studies is 200 to 600 mg per day. Start with 200 mg if you want to test tolerance. It's available over the counter and relatively affordable. The ubiquinol form is better absorbed than ubiquinone, but it's also more expensive. The evidence for ubiquinol being meaningfully better in fertility specifically is limited.
Vitamin D: worth checking, maybe supplementing
Vitamin D receptors are found in the ovaries, endometrium, and placenta, which tells you it has a role in reproductive function. A 2017 meta-analysis in Human Reproduction found that women with sufficient vitamin D levels had higher rates of clinical pregnancy and live birth compared to women who were deficient.
The practical question is whether you should supplement blindly or get tested first. Vitamin D deficiency is common (roughly 40% of US adults have insufficient levels), and a simple blood test (25-hydroxy vitamin D) costs about $30 to $50 without insurance. If you're deficient, supplementing with 2,000 to 4,000 IU per day is standard. If you're not deficient, there's no evidence that extra vitamin D above normal levels improves fertility.
Iron: if your levels are low
Iron deficiency without anemia has been linked to longer time to conception in some studies, and iron deficiency with anemia clearly affects ovulation. A large Nurses' Health Study II analysis found that women who took iron supplements had a lower risk of ovulatory infertility. If your ferritin (iron storage) levels are below 30 ng/mL, supplementation is worth discussing with your doctor. If they're normal, extra iron won't help and can cause constipation and digestive upset.
Supplements that are popular but unproven
Maca root. A Peruvian root that's marketed as a fertility booster, hormone balancer, and energy enhancer. A few small studies suggest it may improve sexual function and mood, but there are no well-designed human trials showing it improves fertility or pregnancy rates. Not harmful, but the evidence that it does anything specific for TTC is thin.
Evening primrose oil. Claimed to improve cervical mucus quality. One small study from 30 years ago showed a possible effect. It has never been replicated. It also may increase the risk of premature rupture of membranes if taken in late pregnancy, though you'd stop before then anyway.
Preseed and fertility lubricants. Not supplements, but worth mentioning: if you use lubricant during sex, standard brands (Astroglide, K-Y) can slow sperm. Pre-Seed and other fertility-labeled lubricants have been tested and don't show the same effect. Mineral oil and canola oil are also sperm-neutral options supported by small studies.
The total supplement stack that makes sense
For a healthy woman under 35 with no known fertility issues: a prenatal vitamin with 400+ mcg folic acid, vitamin D (2,000 IU if untested, or as directed by your doctor based on bloodwork), and CoQ10 (200 to 600 mg) if you're over 30 or want the potential egg-quality benefit. That's three supplements, roughly $30 to $60 per month total. Everything else is optional and should be discussed with your doctor based on your specific situation.
Where to go from here
Nutrition and supplementation work alongside a TTC movement plan. Create a free Catalyst Mom account to get TTC-specific guidance that covers food, movement, and cycle tracking together.
Frequently Asked Questions
Do I really need a prenatal vitamin if I eat a healthy diet?
Yes. Even with an excellent diet, the amount of folic acid that reduces neural tube defect risk (400 mcg daily) is hard to reliably get from food alone. A supplement fills that gap cheaply and safely.
Can supplements replace a healthy diet when trying to conceive?
No. Supplements address specific nutrient gaps. They don't provide the overall dietary pattern that supports fertility (adequate protein, healthy fats, fiber, low processed food). Think of supplements as the backup, not the plan.
Should my partner take supplements too?
Yes. Sperm quality matters, and some of the same nutrients help: CoQ10 has shown benefits for sperm motility in several studies, zinc is important for sperm production, and vitamin D deficiency in men is linked to lower sperm counts. A basic men's prenatal or multivitamin plus CoQ10 is a reasonable starting point.
Is it safe to take multiple supplements at once when TTC?
The three listed above (prenatal vitamin, vitamin D, CoQ10) are safe to take together and don't interact negatively. If you're adding other supplements, check with your doctor or pharmacist, especially if you're also taking medications.
How long before trying to conceive should I start supplements?
Folic acid: at least one month, ideally three. CoQ10: the studies used 60 days of supplementation before fertility treatment, so start at least two months before you want to conceive. Vitamin D: start whenever; it takes weeks to months to build up levels if you're deficient.
