Causes

Infertility causes can affect one or both partners. Sometimes, no cause can be found.

Tubal disorders such as blocked or damaged fallopian tubes, which are in turn caused by untreated sexually transmitted infections (STIs) or complications of unsafe abortion, postpartum sepsis or adhesions because of abdominal/pelvic surgery, endometriosis.
Problems with ovulation are common causes of infertility, accounting for approximately 25% of all infertility cases, such as polycystic ovarian syndrome (which affect the release of eggs from the ovaries) and premature ovarian failure (early menopause, when the ovaries stop working and menstruation ends before age 40) also ovarian disorders which are inflammatory in nature such as endometriosis.
Uterine disorders – such as septate uterus, bicornuate uterus, adenomyosis. Polyps, fibroids cause infertility by blocking the fallopian tubes or stopping a fertilized egg from implanting in the uterus.
Disorders of the endocrine system causing imbalances of reproductive hormones. Examples of common disorders include pituitary cancers and hypopituitarism, hypothyroidism and hyperthyroidism.

Obstruction of the reproductive tract commonly due to injuries or infections of the genital tract; certain genetic diseases such as cystic fibrosis causing dysfunctionalities in the ejection of semen.
Problems with the delivery of sperm due to sexual problems, such as premature ejaculation and erectile dysfunction.
Abnormal sperm production or function due to enlarged veins in the testes (varicocele), undescended testicles, medical disorders such as diabetes, or infections such as chlamydia, gonorrhea, mumps or HIV also can affect the quality of sperm.
Overexposure to certain environmental factors, such as pesticides and other chemicals, and radiation. Cigarette smoking, alcohol, marijuana, anabolic steroids, frequent exposure to heat such as hot tubs, medical treatments such as chemotherapy or radiation for cancer, impair sperm-producing cells.