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Male Infertility
Normal fertility
"Normal" fertility could be defined as conception occurring within a 12 – 15 month period of regular unprotected sex.
Fertility is a highly complex process and infertility can be attributed to either male or female factors, or both. A male must produce semen that contains sufficient numbers of healthy motile sperm, and have the ability to achieve erection and ejaculate semen into the vagina.
The male genital tract includes the testes, the epididymis, the vas, the prostate and urethra. The testes, situated in the scrotum, are mainly made up of loops of fine tubes (seminiferous tubules) which produce the sperm. The sperm cells mature as they pass through the epidiymis (a narrow system of tubes on the surface of the testes). The vas is a hollow tube, which carries the sperm from the epididymis to the urethra.
It takes 3 - 4 months for sperm to develop, during which time production may be affected by febrile illness, exposure to drugs, toxins, radiation, local trauma or infection.
The primary laboratory test for male fertility is "semen analysis". The sample is obtained by masturbation or collected from a special condom following intercourse. Sterile containers must be used to collect the sample following three days of sexual abstinence.
A normal assessment should show:
• Semen volume - 2-4mls
• Sperm count - more than 20 million per ml
• Sperm motility - more than 50% moving
• Sperm morphology - more than 30% of normal shape
• White blood cells - should be less than 1 million per ml
• Anti-sperm antibodies test - should be negative
Common male infertility problems
A single sperm consists of a head, which contains the man's genetic information, and its tip (acrosome) which will help the sperm penetrate the outer shell of the egg; a midpiece, which supplies the energy needed for movement; and the tail which propels the sperm forward.
In order for sperm to be “normal”, the sperm count, motility and appearance must be within certain parameters. Male subfertility can occur due to oligospermia (low sperm count), asthenospermia (poor motility) or teratospermia (high incidence of abnormal forms).
Immunological factors can also affect male fertility. Anti-sperm antibodies may occur following surgery, trauma or infection of the genital tract. These antibodies impair sperm motility and affect the sperm’s ability to penetrate and fertilise and egg.
In some cases, azoospermia (the absence of sperm) can occur. This may be due to an obstruction in the vas, epididymis, or even the testes, or to a bilateral congenital absence of the vas. Azoospermia could also be due to testicular failure caused by hormonal or chromosomal abnormalities, previous infection such as mumps or undescended testes.
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Assisted reproductive techniques for male infertility
Intrauterine Insemination (IUI) combined with superovulation using washed sperm is often effective in the case of mild abnormalities in sperm parameters.
In Vitro Fertilisation (IVF) requires fewer motile sperm because natural transport barriers are bypassed, and sperm come in contact with multiple oocytes from superovulation.
Intacytoplasmic Sperm Injection (ICSI) has revolutionized the treatment of severe male factor problems, especially when the sperm is surgically retrieved. One single sperm is injected into each egg, with a fertilisation rate of around 70%.
In severe cases of male factor infertility, azoospermia, or genetically transmitted diseases, Donor Sperm Insemination (DI) is an option.
Surgical Sperm Retrieval (SSR) is a technique for collecting immature sperm directly from the vas, epididymis or testes. Sperm retrieval may be performed under local anaesthetic or under general anaesthetic, especially during an operation to repair an obstruction in the vas. The sperm are withdrawn from the vas, epididymis and the testes using a fine needle and gentle suction.
Percutancous Epididymal Sperm Aspiration or Testicular Sperm Extraction may be used in cases where sperm are not found. A sample of tissue (testicular biopsy) can be taken from the testes through a small incision. Once the sperm have been collected fertilisation is achieved using ICSI. Excess sperm can be frozen for future use.
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Counselling
Counselling is available to all patients at The LWC, and can be arranged for individuals or couples. The HFEA considers counselling to be a key element in the provision of infertility services, and has made implication counselling a requirement in the case of sperm or egg donation. We offer support counselling at all times. Appointments can be booked via the nurses.
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