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 sperm are produced by the testis, stored in the epididymis (the structure next to the testis in the scrotum) and transferred through the vas deference to the urethra during ejaculation. It takes about 100 days for sperm to develop, during which time production may be affected by febrile illness, exposure to drugs, toxins, radiation, local trauma or infection.
Each 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.
Low sperm count, poor motility and/or high percentage of abnormal forms can cause infertility. 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 there is no sperm in the ejaculate (azoospermia). This may be “obstructive” due to an obstruction in the vas, epididymis or bilateral congenital absence of the vas. PESA is a microsurgical technique using a fine needle to aspirate seminal fluid from behind the obstruction. Azoospermia could also be due to insufficient or lack of production of the sperm because of testicular failure. The latter could be caused by hormonal or chromosomal abnormalities, previous infection such as mumps or undescended testes. TESA is the fine needle technique to aspirate testicular tissue and search for testicular sperm.
At the Fertility Academy we have years of experience in PESA and TESA and many healthy babies have been delivered in our unit following sperm aspiration.