Infertility and the Immune System

The body's immune system is our first and major line of defense against diseases and invading germs. It is comparable to soldiers stationed at the borders of a country, always ready to defend against any form of attack. The body's immune system has the intelligence to differentiate between the normal body cells and foreign/invading cells. It can trigger off a local or widespread alarm response or attack against invading microbes. It can also keep memories of these offending cells, so that it can repel them if they ever show up next time. The body's immune system works like a perfectly set up machine. However, it does have its shortcomings. There may be times when, for some reason, it breaks down and leaves the body at the mercy of invading microbes. There could also be times when the ability to differentiate between body cells and foreign cells goes sour and the immune system will turn its arsenal of attack against normal healthy body cells it is suppose to protect, causing damage to the body system.

The immune system plays a vital role in normal body functioning and the reproductive system is not excluded. Several cells of the immune system help in the reproductive process. For example, some inflammatory cells and their secretory products are important in ovulation and in the preparation of the endometrium of the uterus for the implantation of the fertilized egg. It is therefore not surprising to learn that any dysfunction of the immune system would interfere with the normal reproductive process and by extension, fertility.

As a matter of fact, it is estimated that up to 20% of otherwise 'unexplained' infertility in couples have an immune factor involved. There is not so much scientific evidence to link immune factors to infertility; however, there is a solid scientific evidence to implicate the formation of antibodies against sperm cells as an important infertility factor.

Normally, the sperm cells are protected from the reach of the immune system by tight connections between the cells lining the male reproductive tract, a natural protective mechanism known as the 'Blood Testes barrier'. This protects the testes from having any contact whatsoever with the blood, where the majority of immune cells are housed. Any injury or condition that compromises this barrier gives the immune cells access to the sperm cells. The immune system, not familiar with these sperm cells, because of the barrier separating them, treats the sperm cells as foreign cells and anti sperm antibodies may be formed.

Anti sperm antibodies tend to be commoner in infertile men. Almost 10% of all infertile men have anti sperm antibodies compared to about 1% of fertile men.

The most profound risk factor happens to be surgery on the reproductive tract. Nearly 70% of all men who have undergone a vasectomy reversal would have anti sperm antibodies present on their sperm. Other factors that may also contribute to this condition include:

- Varicocele or dilation of the veins surrounding the spermatic cord
- Testicular torsion or twisting of the testicle
- Undescended testes
- Cancer of the testes
- Infections like prostatitis
- Inguinal hernia surgical repair, especially before puberty.

It is amazing to note, however, that several men with anti sperm antibodies have none of these conditions. This shows that every man with fertility problems is at risk of this condition, especially when no other reason has been diagnosed for the infertility.

Women also stand a risk of anti sperm antibodies. It is believed that about 5% of women with fertility problems could have these antibodies. What is not clear is who is at risk for their formation. Fortunately, intra uterine insemination, which involved placing 'treated sperm cells' into the uterine cavity of a woman, has not been shown to cause the formation of anti sperm antibodies.

The immune system has also been found to affect the ability to carry pregnancy in some women. In women with recurrent pregnancy loss, there is a group of antibodies that appear to attack an early developing pregnancy, resulting in either a miscarriage or severe preeclampsia with risk of intrauterine growth retardation or even foetal death. These antibodies are collectively called anti phospholipid antibodies and testing for them should be an integral part of the work up for recurrent pregnancy loss. It is still unclear if these antibodies affect the ability to get pregnant, but some physicians are of the opinion that the presence of these antibodies may decrease the chances for pregnancy through an invitro fertilization.

There are still several controversial areas as regards immunological factors and infertility. However, what is clear is that the immune system really does affect your fertility when things go wrong.

Michael Russell
Your Independent guide to Infertility

How Pelvic Infections Cause Infertility

The pelvis is very important in female reproduction because it houses most of the reproductive organs. Due to this same fact, pelvic inflammatory diseases (PID) have been known to be a frequent cause of infertility among women. In most cases, the infection of the pelvis starts off as a sexually transmitted disease (STD) caused by either gonorrhoea or chlamydia infections of the cervix. These infections are usually without symptoms, or in worst cases, cause some cervical discharge. The bacteria responsible for these infections could, from the cervix, ascend into the uterus and fallopian tubes causing a painful infection and an accumulation of pus in the tubes.

The ascension of the infection can be stooped by the use of antibiotics in the early stages, though, the normal body defence, with or without antibiotics, will act by forming a walled-abscess over, and to contain, the infectious bacteria. The abscess will eventually resolve in either of two ways. The abscess cavity would either become sterilized, the fluid eventually cleared and the abscess then goes away, which is better, or it ruptures and the infection then spreads further to cause more abscesses, which is very bad for fertility.

To get a better picture of how pelvic diseases affect fertility, you should note that, once a pathogenic bacteria such as gonorrhoea or chlamydia gets access above the cervix to the uterus and uterine tubes, if not stopped by the use of antibiotics or arrested by the body's immune system, the inside surfaces of the tubes become denuded of their skin called the epithelia lining. Several white blood cells, in their attempt to contain the infection, form a closed cavity around the pathogenic bacteria. This space becomes so filled with the multiplying bacteria and fluids that that area of the tube become filled with pus.

Even if treated at this stage, the damage has been done. The destroyed lining of the tube may cause gluing together of the walls of the tube, causing blockage of the tube later, to both egg and sperm cells. For pregnancy to occur, the sperm cells and the ovum must meet in the tubes for fertilization to occur and the product of fertilization must be transported from the tube to the uterine cavity on time for implantation. So, even if the tubes don't get blocked by agglutination of their walls due to stickiness caused by past infections, the destruction of the tubal lining still affect fertility because the ciliary wave motion of the tubes that serve to move the fertilized ovum down to the uterus right on time for implantation, is lost.

What could be worst is that, if the tubal abscess opens or leaks from the end of the tube, the ovary at that end of the tube may stick to the tube and become the far wall of another abscess cavity, which is now bigger and more destructive. This is called a tubo-ovarian abscess and it causes a complete obliteration of fertility on the side it occurs, since the tube, ovary and all its eggs are destroyed.

It is estimated that 5-10% of women with PID develop the most severe form, tubo-ovarian abscess. Women with this condition tend to be older (in their thirties and forties) and they also suffer severe pain and probably nausea, vomiting and abdominal distension.

Although, apart from untreated sexually transmitted diseases, tubo-ovarian abscess can also arise due to some other factors and these include:

- Post pelvic surgery - Uterine perforation at the time of D&C or any vaginal procedure - Bowel perforation following ruptured appendicitis - Bowel perforation following diverticulitis - Pelvic malignancy

Pelvic inflammation disease that has degenerated into abscess cavities is usually treated initially with a broad spectrum antibiotic. The abscess is usually seen as a mixed infection, because, though, the initial infection is often from a STD bacteria, multiple different bacteria from the bowel tract may become involved in the abscess due to transmigration across swollen, inflamed bowel walls surrounding the abscess area. Usually, at least two to three different antibiotics are required immediately diagnosis is made. If the infection doesn't improve, usually within 72hours, then some sort of surgical drainage of the abscess is required. If all these fail, then as a last resort, exploratory surgery removing all of the infected tissue is carried out.

Michael Russell
Your Independent guide to Infertility