Recurrent miscarriage, main causes

La World Health Organization It defines abortion as the spontaneous interruption of pregnancy before the fetus is viable, that is, before the fetus weighs 500 grams, which corresponds to week 20-22 of gestation. The incidence of abortion in the general population is approximately 15% and increases with the patient's age.
We use the term “repeat abortion” to refer to patients who have had two or more non-voluntary terminations of pregnancy, either consecutively or alternately.
The likelihood of experiencing another miscarriage in couples who have had a first pregnancy loss increases to 18%. After two previous miscarriages, the probability exceeds 25%.

What are the causes of recurrent miscarriages?
Up to 50% of cases are attributed to unknown causes, but the rest may be justified by other types of causes that become evident after an exhaustive study and, therefore, could be avoided.

– Genetic causes:
A karyotype determination is performed on peripheral blood in both members of the couple to rule out the existence of chromosomal abnormalities.

– Anatomical alterations:
Abnormalities of the uterine cavity can cause recurrent miscarriages in some patients. In these cases, treatment of adhesions, uterine septa, or septa that deform the uterine cavity is recommended.
These alterations are detected through imaging tests such as ultrasounds, hysterosalpingograms, sonohysterograms or hysteroscopies.
– Thrombophilias:
Clotting factors can cause recurrent miscarriage. This encompasses a group of conditions characterized by an imbalance between the coagulation and fibrinolysis systems. They are detected through blood tests and can be treated with anticoagulants.
– Endocrinopathies:
There are elements that, if controlled, do not have to pose a risk factor, such as diabetes or thyroid dysfunction.
– Immunological disorders:
“Immune tolerance” is crucial at the time of implantation; it means that the immune system does not recognize the embryo as foreign and allows it to implant. If this tolerance is disrupted, the embryo may be recognized as a foreign body and the organism may react against it.
– Male factor:
Various tests can be performed to chromosomal study of sperm: FISH, sperm DNA fragmentation test or, if necessary, a meiosis study in testicular biopsy.

Recently, the European Society of Human Reproduction and Embryology (ESHRE) has published a guide on recurrent miscarriage which can be downloaded in full at the following link: ESHRE RPL Guideline_28112017_FINAL

From InebirWe recommend that all couples who have suffered two or more miscarriages seek the help of specialists to begin a fertility study. Our team approaches each case from a multidisciplinary perspective and individualizes each study depending on factors such as age, previous history, lifestyle, weeks of pregnancy at which the abortion occurred, the anxiety of the couple, etc.