What is female infertility?
Female infertility is a condition that prevents women from becoming pregnant, which is diagnosed when a woman is unable to get pregnant after 1-2 years of fertile sexual intercourse, even though it might still be possible for her to conceive. The loss of reproductive capacity is linked to age; in fact, the chances of conceiving decrease in time after age 30. Together with age, there are different causes that may determine infertility like lifestyle, search for the first child at a late age, drug use, alcohol abuse, smoking, working conditions, pollution and also genetic causes.
What are the possible genetic causes of female infertility?
Genetic causes of female infertility are related to damages of the chromosomal structure, which is a DNA strand that contains genes. Examples of chromosomal damages are the so-called “Robertsonian translocations”, in which chromosomes come together and both lose a part. This happens because two chromosomes stay together in a person and the gametes of these individuals will then be carriers of an additional copy of a certain chromosome (trisomy) or of one copy less (monosomy). These translocations lead to an increase in the risk of spontaneous abortion and therefore to a reduction of fertility. Histocompatibility antigens are another genetic cause of infertility. These antigens are molecules present on the membrane of cells and are different between people. When the immune system detects a molecule that is different from its own, it eliminates the relative cell. This is the reason why histocompatibility antigens play a crucial role in increasing maternal tolerance towards the embryo and therefore the chances of pregnancy. Genetic intolerances can also lead to infertility or to multiple abortions because the intake of food that is not tolerated causes chronic inflammation and an exaggerated immune response that can be damaging for the maturation of eggs. Last but not least, smoking can lead to mutations of oncogenes, which can induce the transformation of a healthy cell into a tumour cell both in the mother and in the embryo.