Male infertility problems
Sperm are produced in the seminiferous tubules of the testes, from where they move to be matured and stored in the epididymis. This process takes approximately three months to complete. During sexual intercourse the sperm leave the epididymis and travel through the vas deferens where they are mixed with fluid secreted from various glands. This mixture of sperm and seminal fluid (semen) is then deposited in the vagina of the female partner following ejaculation.
Causes of male infertility can be divided into two categories; physical abnormalities of the male reproductive tract, such as epididymal or vas obstruction or impaired sperm production and secondly, abnormalities of the sperm themselves. However, in most cases of male infertility the cause is unknown.
To determine male fertility we carry out a semen analysis where we test the number, activity and shape of the sperm. A normal assessment should show a sperm count of more than 20 million sperm per millilitre with at least 50% of the sperm actively moving and more than 30% of the sperm of normal shape. They must be capable of moving through the female genital tract to reach the fallopian tube where the egg is fertilised, and so must survive for a period of 24-48 hours.
Common male infertility problems are due to the following:
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Abnormal sperm parameters
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Azoospermia (no sperm in the ejaculate)
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Antisperm antibodies.
Abnormal sperm parameters
Abnormalities in the semen are primarily due to a defect in sperm production by the testicles.
The cause of this is usually unknown but occasionally may be associated with previous infections, surgery or excessive drinking. Certain drugs, radiation and radiotherapy may have a detrimental effect on the production of sperm. The presence of a varicocele may lead to a rise in the temperature around the testicles, which may adversely affect sperm production and motility.
Azoospermia
The absence of sperm in the ejaculate (azoospermia) may be due to an obstruction at the level of the vas deferens, epididymis, or even at the level of the testes. It may also be due to bilateral congenital absence of the vas. Some men might have testicular failure, i.e. failure of production of sperm. This may be the result of a chromosomal disorder or previous infections such as mumps. It may also be associated with a history of undescended testes. Occasionally azoospermia is due to a lack of hormonal stimulation of the testes by the pituitary gland. This can be diagnosed by hormone blood tests and may be treated with hormone therapy. A testicular biopsy may be recommended to determine whether any sperm are being produced by the testes that could be used in IVF/ICSI treatment.
Antisperm antibodies
There may be antisperm antibodies in the semen which bind to the sperm and impair their motility and their ability to penetrate and fertilise an egg. Antibodies arise following reversal of a vasectomy or other surgery on the male genitals and may also be related to previous infections or injury.
Until recently there has been no effective treatment for the majority of male infertility problems discussed above. Drugs rarely improve sperm counts. However, since the introduction of micromanipulative techniques, in particular Intra-Cytoplasmic Sperm Injection ( ICSI ), the success rates for couples with male infertility problems have markedly improved. Another option available to the couple is to use sperm from a donor (IUID).
