SOME OF THE REASONS FOR LOW SEMEN PARAMETERS:
Primary Testicular Disorders
Here the fault lies at the testicular level, despite the presence of a normallv-functioning hypothalamic-pituitary complex and include:
i. Chromosomal disorders, e.g. Klinefelter’s syndrome in which the cells contain 47 chromosomes (44 autosomes and XXY sex chromosomes).
ii. Immotility due to absence of dynein arms in the sperm tail. This occurs in some disorders including the Kartagener syndrome where the motility of all body cilia is impaired leading also to sinusitis and bronchitis.
iii. Cryptorchidism or undescended testes: If this condition is not treated properly in early life (hormonal and/or surgical treatment), the affected testis may never acquire its full spermatogenic capacity.
iv. Physical and chemical agents: Spermatogenesis is inhibited by irradiation of the testes, the use of cytotoxic drugs, cimetidine (which competitively inhibits androgens), sulphasalazine (reversible on discontinuation), spironolactone (which blocks androgen receptors). Spermatogenesis is also inhibited by acute and chronic heavy metal poisoning (e.g. lead, arsenic, zinc, mercury), accidental inhalation of insecticides (1,2 dibromo-3-chloropropane, DBCP), herbicides (paraquat) or sterilization gas (ethylene oxide). Sperm motility is inhibited
by the use of propranolol and other beta blockers, nitrofuranes, niridazole (an antischistosomal) and ethanol (which produces relative deficiency of vitamin A).
v. Orchitis (traumatic and infective): In particular mumps occurring in adult males may lead to permanent testicular damage.
vi. Chronic illness General ill health will lead to deranged spermatogenesis, e.g. diabetes, hypothyroidism, malignancies and other debilitating diseases.
vii. Varicocele. The optimum temperature for spermatogenesis is 29-35 °C and this is achieved by the extra-abdominal location of the testes. It is thought that the presence of a varicocele leads to an increased temperature of the testes with its suppressing effect on spermatogenesis
Recently, however, the relation between varicoceles and male infertility has been challenged (Vermeulen and Vandeweghe, 1984; Baker et al, 1985).
viii. Immunological disorders where antisperm antibodies lead to inhibition of spermatogenesis. Antisperm antibodies may be produced following infection or trauma to the testis and in patients who had reversal of sterilization with a long vasectomy-reversal time lapse.
ix. An idiopathic group remains in which no specific cause for the testicular disorder can be found.
Duct Obstruction
Here the fault lies in the excretory ducts of the male genital system, despite the presence of a normally functioning hypothalamic pituitary testicular axis. The obstruction may be congenital or may follow chronic infection.
Accessory Gland Disorders
These may be due to congenital absence of the vas and/ or seminal vescicles or due to chronic infection (i.e. prostatitis or seminal vesiculitis) leading to an increased number of WBCs and other inflammatory cells. The semen contains debris and pus cells which may affect the normal function and motility of the spermatozoa
Primary Testicular Disorders
Here the fault lies at the testicular level, despite the presence of a normallv-functioning hypothalamic-pituitary complex and include:
i. Chromosomal disorders, e.g. Klinefelter’s syndrome in which the cells contain 47 chromosomes (44 autosomes and XXY sex chromosomes).
ii. Immotility due to absence of dynein arms in the sperm tail. This occurs in some disorders including the Kartagener syndrome where the motility of all body cilia is impaired leading also to sinusitis and bronchitis.
iii. Cryptorchidism or undescended testes: If this condition is not treated properly in early life (hormonal and/or surgical treatment), the affected testis may never acquire its full spermatogenic capacity.
iv. Physical and chemical agents: Spermatogenesis is inhibited by irradiation of the testes, the use of cytotoxic drugs, cimetidine (which competitively inhibits androgens), sulphasalazine (reversible on discontinuation), spironolactone (which blocks androgen receptors). Spermatogenesis is also inhibited by acute and chronic heavy metal poisoning (e.g. lead, arsenic, zinc, mercury), accidental inhalation of insecticides (1,2 dibromo-3-chloropropane, DBCP), herbicides (paraquat) or sterilization gas (ethylene oxide). Sperm motility is inhibited
by the use of propranolol and other beta blockers, nitrofuranes, niridazole (an antischistosomal) and ethanol (which produces relative deficiency of vitamin A).
v. Orchitis (traumatic and infective): In particular mumps occurring in adult males may lead to permanent testicular damage.
vi. Chronic illness General ill health will lead to deranged spermatogenesis, e.g. diabetes, hypothyroidism, malignancies and other debilitating diseases.
vii. Varicocele. The optimum temperature for spermatogenesis is 29-35 °C and this is achieved by the extra-abdominal location of the testes. It is thought that the presence of a varicocele leads to an increased temperature of the testes with its suppressing effect on spermatogenesis
Recently, however, the relation between varicoceles and male infertility has been challenged (Vermeulen and Vandeweghe, 1984; Baker et al, 1985).
viii. Immunological disorders where antisperm antibodies lead to inhibition of spermatogenesis. Antisperm antibodies may be produced following infection or trauma to the testis and in patients who had reversal of sterilization with a long vasectomy-reversal time lapse.
ix. An idiopathic group remains in which no specific cause for the testicular disorder can be found.
Duct Obstruction
Here the fault lies in the excretory ducts of the male genital system, despite the presence of a normally functioning hypothalamic pituitary testicular axis. The obstruction may be congenital or may follow chronic infection.
Accessory Gland Disorders
These may be due to congenital absence of the vas and/ or seminal vescicles or due to chronic infection (i.e. prostatitis or seminal vesiculitis) leading to an increased number of WBCs and other inflammatory cells. The semen contains debris and pus cells which may affect the normal function and motility of the spermatozoa