Fertility Decoded

Supplement evidence checker

Vitamins, minerals, and herbs sold as fertility supplements — anything you might buy over the counter or be told to take before or during treatment. Here is what the evidence actually shows for 24 of the most common ones, including where the evidence for "it works" is thin and where a supplement carries a documented safety risk of its own.

Check a supplement you were offered

Standard preconception care

Cochrane-reviewed

Other common supplements

Ayurvedic herbs — a safety brief

These are heavily marketed in India specifically to people trying to conceive, in early pregnancy, or breastfeeding. Several have real, peer-reviewed safety findings independent of whether they work — we're covering them because you're likely to be offered one, not because we recommend them.

Ashwagandha (Withania somnifera)Documented, NIH-recognized risk of serious liver injury (including deaths in patients with pre-existing liver disease) — this outweighs the sperm-count promise from a single, since-delisted-journal trial. Avoid entirely with any liver condition; discuss with a doctor otherwise.
Documented harm
Shatavari (Asparagus racemosus)An animal pregnancy-exposure study found estrogenic tissue changes on the exact gestation window a trying-to-conceive user could unknowingly be in; its main real-world use (as a lactation aid) rests on weak or manufacturer-funded human evidence, not independent proof it works.
Documented harm
Tribulus terrestris (Gokshura)Multiple peer-reviewed case reports of severe liver and kidney injury exist alongside some evidence for sperm parameters in infertile men — this is a real safety trade-off, not a minor caveat. Testosterone-boosting claims are separately not well supported.
Documented harm
Safed Musli (Chlorophytum borivilianum)Popular traditional aphrodisiac; evidence for effectiveness is limited to animal studies — no human clinical trials found — but a dedicated safety check found no documented human liver-injury signal and reassuring (if limited) toxicity/contamination data, unlike several of the other Ayurvedic herbs in this list.
Contamination risk
ShilajitA few small, manufacturer-funded human trials show promising sperm/testosterone effects; as a mineral product its heavy-metal risk is a sourcing/geology issue, not a processing one — third-party heavy-metal testing matters more here than for any other item in this list.
Contamination risk

Other flagged items

Last reviewed . Sources on each supplement's page.