NAC has shown positive effects on parameters of both male and female infertility.
NAC may improve sperm health and quality (e.g., motility, concentration, morphology, volume) in infertile men, likely through reductions in oxidative stress in the testicular tissue and semen. However, NAC hasn’t consistently been found to influence hormones involved in male fertility (testosterone, luteinizing hormone, follicle stimulating hormone (FSH), and prolactin).[1]
In women with infertility due to polycystic ovarian syndrome (PCOS), NAC may reduce testosterone and increase follicle stimulating hormone levels.[2] Compared to placebo, NAC seems to increase rate of pregnancy and ovulation rates, but not when compared to metformin (a medication commonly used in PCOS).[3]