Male InfertilityIf a couple is unable to conceive after at least one year of unprotected intercourse, physicians recommend that they be assessed for fertility problems. In men, hormone disorders, illness, trauma to the reproductive organs, obstruction, and sexual dysfunction can temporarily or permanently affect sperm and prevent conception.
Incidence and prevalence
According to the National Institute of Health, there are 2.6 million infertile couples in the United States, and male infertility is involved approximately 40 percent the time. Of that group, 50 percent are never able to father children, while 50 percent have a treatable medical condition.
Causes and Risk Factors
The primary causes of male infertility are impaired sperm production, impaired sperm delivery, and testosterone deficiency. Other causes include
- Defect or obstruction in the reproductive system, such as failure of the testes to descend into the scrotum or the absence of one or both testicles
- Diseases such as cystic fibrosis, sickle cell anemia, or sexually transmitted diseases
- Hormone dysfunction, mainly testosterone deficiency caused by a disorder in the hypothalamic-pituitary-gonadal axis
- Infections like prostatitis, epididymitis, and orchitis, which can cause irreversible infertility if they occur before puberty
- Testicular trauma, resulting from injury, surgery, or infection can trigger an immune response in the testes that may damage sperm. Though their effects are not fully understood, antibodies can impair the ability of sperm cells to swim through cervical mucus or to penetrate a female egg.
- Medications to treat high blood pressure and digestive diseases
- Metabolic disorders such as hemochromatosis, which affects how the body uses and stores iron
- Systemic diseases including high fever, infection, kidney disease
- Testicular cancer
- Varicocele, which is a mass of enlarged veins that develops in the spermatic cord leading from the testicles to the circulatory system. If the valves that regulate bloodflow from these veins become defective, blood does not circulate efficiently, causing swelling in the veins above and behind the testicles. Impaired circulation keeps the blood warm, which increases the temperature of the testes. Heat can damage or destroy sperm and possibly also impede production of new, healthy sperm, leading to infertility.
- Retrograde ejaculation, which occurs when impairment of the muscles or nerves prohibit the bladder neck from closing during ejaculation. This causes semen to flow backward into the bladder, prohibiting fertilization. This disorder has a variety or origins, including bladder surgery, congenital defects in the urethra or bladder, or diseases that affect the nervous system. Diminished or "dry" ejaculation and cloudy urine after ejaculation are signs of this condition.