When your immunity prevents pregnancy or How antibodies can complicate conception

News 12. April, 2022

Immune system disorders are behind a significant proportion of spontaneous abortions. They are also one of the relatively common causes of infertility. There may be several reasons why the immune system, initially oriented towards the body’s defenses, turns against our body‘s natural processes. Modern reproductive medicine can already detect the vast majority of them and help couples who want to have a baby to overcome this difficulty. However, it is essential to solving the problem in time, says Kateřina Veselá, a doctor and director of Repromeda reproductive clinic.

There are dozens of factors behind unsuccessful attempts to conceive or bear a baby. In addition to an unhealthy lifestyle, genetic indispositions, or advanced age, poorly functioning immunity is also a common cause. This should protect our body against pathogens and remove foreign pollutants and old or damaged cells. However, in some cases, the eggs, sperm, placenta, or embryo become the target of unwanted immune processes.

When to beware?

Pregnancy is an immune-complex situation from a certain point of view. The fetus is de facto half foreign tissue for the mother, and the maternal organism must tolerate the fetus during pregnancy for everything to go well. Malfunctions can occur in such a complex regulatory system.

Infertility caused by an inadequate immune system response often occurs in women who already suffer from an autoimmune disease. Typically, this may be one of many so-called “rheumatic diseases,“ such as juvenile idiopathic arthritis, systemic lupus erythematosus, thyroid disorders, and diabetes. However, it can also be caused by recurrent inflammation of the genital organs. Incorrectly programmed immunocompetent cells can also complicate conception in diseases like endometriosis.

In practice, poorly set immunity can manifest itself in a woman as an aggressive reaction against reproductive cells, whether these are her eggs or her partner’s sperm, which understandably hurts the processes necessary for fertilization. Not only antibody immunity but also cellular immunity can play a crucial role. However, each disease has its specificities and can also have different consequences for fertility.

While some disorders prevent fertilization and embryo implantation or cause early miscarriage, other diseases do not affect the ability to conceive but cause fetal compromise and miscarriage or premature birth.  This is especially the case when the placental vascular system becomes the target of autoimmune reactions and blood flow parameters are impaired, significantly increasing the risk of blood clots and leading to fetal growth retardation or even pregnancy loss.

Although immune causes of infertility are significantly more common in women, they do not avoid men either. This may also be due to autoimmune disease. Antibodies can bind directly to the sperm heads and cause them to clump together, preventing their further movement and penetration into the egg. Damaged immunity also “attacks” the actual spermatogenesis, i.e., the production of sperm, in some men. Autoimmune disorders of sperm production are also more common in men who suffer from some systemic immune disease.

How to outsmart immunity

Fortunately, even insidious immunological causes of infertility can now be overcome in many cases. Extracorporeal fertilization methods are very successful, specifically if sperm is injected into the egg, thus bypassing any immunological block. Similarly, some preparations can improve the prospects of embryo implantation if the implantation process is immunologically affected. Rare cases of the so-called antiphospholipid syndrome, which leads to miscarriage in the later stages of pregnancy or premature birth, can be addressed by administering immunoglobulins.

If either partner suffers from an autoimmune disease, it is essential to consult a specialist about the planned process of conceiving a baby. Several diseases of the immune system do not necessarily reduce fertility. However, they can manifest themselves to an increased degree during pregnancy when a woman’s defenses are under high stress. The health of the unborn baby is at risk, but also that of the woman herself.

It is also essential not to delay the problem, as some autoimmune diseases can cause premature menopause and unexpectedly end a woman’s fertile period. A timely visit to a specialist can prevent this. The usual recommendation for women who delay pregnancy is to have their eggs frozen at the optimal fertile age at a reproductive clinic. If any complications then arise in the future, this step can save a woman’s chances of conceiving a baby.