Infertility may be due to male or female factors. Causes of infertility in women include ovarian factors, tubal factors, age-related factors, uterine problems, PCOS, endometriosis, etc. The menstrual cycle can be affected by many factors, such as diet, emotional instability, lifestyle, and stress responsible for creating an imbalance of the Doshas (control the activities of the body-Vata, Pitta and Kapha).
Male infertility is usually caused by problems that affect either sperm production or sperm transport which includes varicocele, infections, ejaculation problems, tumors, hormone imbalances, defects of tubules that transport sperm, etc.
In Ayurveda the main cause of any abnormal function in the body is agnimandya (vitiation of the digestive fire of the body) & tridosha dushti (vitiation of three governing factors of the body) which is also one of the reasons for infertility.