MALE INFERTILITY
Male infertility refers to the inability of a male to achieve a pregnancy in a fertile female. In humans it accounts for 40-50% of infertility. Male infertility is commonly due to deficiencies in the semen quality.
Factors that cause male infertility
Pre-testicular factors refer to conditions that impede adequate support of the testes and include situations of poor hormonal support and poor general health including :
- Deficient growth of gonads due to various causes
- Drugs, Alcohol, Smoking.
- Strenuous exercises like bicycle riding and horse riding.
- Medications affect spermatogesis e.g. steroids, chemotherapy. These decrease FSH levels and affect sperm quality.
- Genetic abnormalities.
Testicular factors refer to conditions where the testes produce semen of low quantity and/or poor quality despite adequate hormonal support :
- Genetic abnormalities.
- Abnormal set of chromosomes.
- Cancers of the testis.
- Undescended testis during birth.
- Varicocele (Increase in the size of the vessels in the scrotal sac causes increased temperature around the testis).
- Trauma.
- Hydrocele.
- Mumps.
- Malaria.
- Testicular infection (Orchitis).
- Radiation to the testis decreases its function.
Post-testicular factors decrease male fertility due to conditions that affect the male genital system and include defects of the genital tract as well as problems in ejaculation. Here the testicular sperm production is normal :
- Vas deferens obstruction.
- Drugs, Alcohol, Smoking.
- Absence of Vas deferens from birth.
- Infection eg. Prostatitis.
- Retrograde ejaculation.
- Hypospadias.
- Impotence.