Repeated miscarriages are one of the most traumatic experiences an assisted reproduction couple can face. Therefore, it is essential to identify the causes and avoid the suffering of the parents. In many cases, the origin of these miscarriages is unknown, although in 50% of the cases it is usually found in genetics and antiphospholipid syndrome (APS).
What are repeated miscarriages?
A repeated miscarriage occurs when a couple has had three or more gestational losses before 20 weeks of pregnancy. However, after the second miscarriage, a study is usually performed to detect the cause of repeated miscarriages.
In addition, biochemical pregnancies, also called micro-miscarriages or biochemical miscarriages, could also be taken into account in assisted reproduction patients. The causes of these repeated miscarriages can be diverse:
Proven causes of repeated miscarriages.
- Genetic causes: the main cause of repeated miscarriages, accounting for 50% of cases. Most genetic alterations are due to the woman’s age and the increase in the percentage of eggs with chromosomal alterations (especially after the age of 40). Also, alterations in the chromosomal endowment of the parents or genetic problems in the sperm could be genetic causes.
- Antiphospholipid syndrome (APS): affects 10-15% of repeated miscarriages, due to thrombus formation at the level of the placenta or due to altered hormone production resulting in abnormal placental development.
Probable causes of repeated miscarriages, but not demonstrated
- Thrombophilias: Thrombophilias, alterations in the coagulation system, could increase the risk of miscarriage. However, studies do not agree when it comes to identifying which are the ones that could cause a repeat miscarriage. Therefore, it is essential for the patient to visit a specialist in assisted reproduction.
- Uterine abnormalities: the presence of polyps, myomas, septa, among other uterine malformations, tend to increase the chances of miscarriage.
Causes of miscarriages that have not been demonstrated as a risk factor
- Endocrine: diabetes and thyroid function disorders are clinically related to repeated miscarriages.
- Infectious: they negatively affect the vagina, in terms of germs, cervix, endometrium and urethra.
- Autoimmune causes: they are susceptible to being a risk factor, specifically those not related to antiphospholipid syndrome.
Causes of repeated miscarriages that are under investigation
- Alloimmune: maternal rejection of the father’s antigens expressed by the fetus.
- Endometrial: histological alterations, embryonic adhesion factors, proteins?
At URH GarcĂa del Real we are aware of the hard experience that repeated miscarriages mean for a couple. For this reason, we carry out a study to find out the causes. We only propose treatments that have been scientifically tested and under the supervision of a specialist.