Reproductive Immunology Investigations & Treatment
Evidence suggests that problems with the functioning of the mother’s immune system can be another factor leading to recurrent miscarriages, failed implantation of the embryo and IVF failure, particularly where perfectly formed embryos are created yet often rejected well before the pregnancy can be detected by the most sensitive of tests.
There has been an increasing success rate gained by treating many cases of previously unexplained infertility or recurrent miscarriage problems by identifying and treating potential immunological factors. Generally, the immune system fights off invading cells that have a different genetic pattern to the body. For example, the invading cells can be viruses or tissues from transplanted organs. The body’s response is to fight off what it considers to be an infection. However, a foetus in the womb also has a different genetic pattern as it carries the father’s genes as well as the mother’s.
In a normal pregnancy, it is thought that mother’s immune system somehow suppresses the body’s normal response to the “invading cells” of the developing foetus. The placenta also appears to play an important part in protecting the embryo from an attack by the mother’s immune system. Studies also propose that proteins in semen may help woman’s immune system prepare for conception and pregnancy. For example, there is a great deal of evidence that prolonged exposure to a partner’s semen through pregnancy can prevent pre-eclampsia, as several immune system modulating factors present in seminal fluid trigger a protective response in the mother.
A successful pregnancy is also dependent upon a complex number of immunological factors designed to convert the mother’s womb into a welcoming environment for the developing foetus and its placenta. When these mechanisms go wrong and, depending upon how and when this happens, there are some treatments that can be tried.
Aspirin
More recent search has found that a low dosage of aspirin appears to increase the chances of pregnancy in women who experience recurrent miscarriages associated with blood clotting disorders, that interfere with the blood circulation of the placenta, by preventing clots from forming.
Studies show that aspirin may also be helpful in increasing pregnancy rates in all women since it appears to increase the activity of the ovaries, allowing them to release multiple eggs during ovulation. It also appears to increase blood flow to the uterus, allowing a thicker and healthier uterine lining to develop.
Heparin
Heparin therapy can help a woman with Antiphosphilipid Syndrome, high levels of antiphospholipid antibodies, carry a pregnancy to term. These antibodies come into play when blood needs to clot, or when a body is cut or bruised, for example, to prevent massive blood loss. However, high levels can disrupt the blood’s clotting mechanism causing clots to form in the placenta, resulting in miscarriage as the clots block the passage of oxygen and nutrients to the foetus resulting in it being rejected. Blood clots can also interfere with the lining of the placenta, making it difficult for an egg to implant.
Heparin is an anticoagulant which helps to thin the mother’s blood, to prevent it from clotting unnecessarily and often given in conjunction with low-level aspirin therapy for infertility treatment, where no other cause for recurrent miscarriage can be explained.
Intra Venous Immune Globulin (IVig)
Immunoglobulins are proteins manufactured in the body that are used to produce antibodies and various other factors which act to modify the immune system’s behaviour. Research has also shown that natural killer (NK cells) produced by the immune system to fight infections, for example, can interfere with the development of the placenta and prevent an embryo from implanting or developing normally, resulting in rejection and subsequent miscarriage. It also appears that individuals with Antiphosphilipid Syndrome are more likely to have elevated NK cells.
IVig is a collection of Y shaped antibodies, taken from donated blood plasma, which have proven to be effective in treating a variety of autoimmune system disorders but now proving to be useful in treating immunologically related infertility problems.
IVig infusion therapy appears to suppress NK cell reactions reducing the risk of implantation failure and allowing a successful pregnancy. The therapy is usually started from the first month of pregnancy and continued monthly until the 28th week of pregnancy.
There is some evidence to suggest that starting IVig infusions before pregnancy occurs may also help to prevent miscarriage. The first infusion is always done in a clinical setting under proper supervision in case any severe reactions to the infusion may occur.