Over the last several years, more attention has been paid to the prevalence of male factor infertility. While infertility was once considered primarily a “female problem,” we now know that up to half of all infertile couples will have some degree of male sub fertility. Given this high incidence, no treatment of the female should be initiated prior to a complete evaluation of her male partner.
Contrary to females, whose reproductive lives culminate in the menopause, males retain the ability to reproduce throughout their lives. In their later years, sperm quality and quantity decline but are still usually sufficient to initiate a pregnancy.
In the most basic terms, a man must be able to produce a sufficient quantity of “quality” sperm that can be ejaculated into the vagina. These sperm must swim through the cervical mucus into the uterus to the site of fertilization, at the end of the fallopian tubes. Once a sperm reaches the ovulated egg, it must be able to penetrate all of the cellular investments surrounding it. Once inside the egg, the sperm’s genetic material must combine with the eggs’ genetic material to produce an embryo.
Sperm are sensitive to temperature changes, and nature devised the scrotum for regulation. When the testicles become “too hot” the scrotum expands to move them further away from the body, and when the temperature is “too low” the scrotum contracts to bring the testicles closer to the body.
Anything that interferes with the scrotum’s function can decrease sperm quantity and/or quality. Since sperm take three months to develop, anything affecting their development today will not be evident until three months later. Activities such as habitual, prolonged sitting in a hot tub can adversely affect sperm as can clothes that are too tight fitting. Some occupations that require prolonged sitting can negatively affect sperm.
Sperm are also affected by environmental factors. Exposure to heavy metals or smoking, for example, have been linked to reduced sperm count or function.
A man can also rarely produce antibodies to his own sperm, usually as a consequence to testicular trauma. His immune system recognizes sperm as invading pathogens and seeks to destroy them.
One common cause of reduced male fertility is the varicocele. A varicocele is a blockage of the vessels in the spermatic cord which normally function to “move and cool” the blood serving the testes. A varicocele can often be repaired surgically by a urologist.
Hormonal causes of male infertility are rare and include hypogonadotropic hypogonadism (insufficient gonadotropin hormones) which will sometimes respond to medical treatment with the fertility drug FSH. Unfortunately, medical treatment of male infertility has not been particularly effective. Clomid® has been tried with limited success. None of the “sperm enhancers” seen on the Internet have demonstrated clinical effectiveness and frankly are a waste of time and money.
Oftentimes we see men who want to have a reversal of a vasectomy because of changes in their “life situation” such as divorce and remarriage. Whether or not the tubes can be reconnected depends upon how they were cut (laser, electrocautery, etc.), where they were cut, and how much of the tubes remain. A skilled surgeon can often reconnect the tubes but vasectomy should always be considered a permanent means of birth control. Men are encouraged to freeze semen samples prior to vasectomy for future use in either IUI or IVF in case their life situation changes.
Intrauterine insemination (IUI) may be indicated in cases of mild male factor infertility but the per cycle success rates are lower than with IVF. Sperm are specially washed and concentrated for the IUI procedure.
Studies demonstrate that the per cycle success rates using in vitro fertilization are higher than after surgical repair of the tubes (vasovasostomy). Micromanipulation procedures, such as intracytoplasmic sperm injection (ICSI) combined with IVF can achieve pregnancy with extremely low numbers of available sperm. Using ICSI, a single sperm is injected directly into each egg.
In fact, pregnancy can still be achieved if there are no sperm in the ejaculate, or if the man cannot ejaculate due to conditions such as spinal cord injury. Sperm are taken directly from the testicles (TESA) or the reproductive tract (MESA). (See the ICSI page for more information).