Before going into the details about the causes of recurrent miscarriages, every woman must know that women with recurrent miscarriages can get pregnant and deliver normally. Technically, a woman is said to experience recurrent miscarriage when she has had three consecutive miscarriages. Around 20% woman experience miscarriage, which means 1 in 5 pregnancies can miscarry. However, when it happens for three times and that too consecutively, it is a cause for concern. Recurrent miscarriages can happen in one in 100 women, meaning there is a just a 1% chance.
What are the causes of recurrent miscarriages?
Basically, in recurrent miscarriages, there can be issues at various levels including the chromosomes to physical problems. Here are the few common causes:
1. Chromosomal abnormalities: In general, an egg from mother and sperm from father fertilise to form an embryo. Hence, the embryo has genes from both the parents. But in some cases, there can be genetic problems known as chromosomal aberrations. The incidence of chromosomal problems in recurrent miscarriages in 3 – 4%. If the mother’s egg is carrying abnormalities in chromosomes, an embryo can form but there can be an early miscarriage. The same happens if there are any chromosomal abnormalities in the father’s genes. However, even if the genes from both the parents are normal, there can still be chance mutations, which can cause recurrent miscarriage.
2. Immune-related problems: Immune related antiphospholipid syndrome — it is one of the most important causes of recurrent miscarriages. In this condition, the mother’s blood has got antibodies which make the blood sticky and thicker, as a result, there are higher chances of clot formation. Usually, the embryo gets stuck to the womb, where blood is supplied through capillaries. However, if you suffer from this condition, the capillaries that supply blood to the embryo will be blocked. As a result, there will be no blood supply, and the embryo will stop growing, causing miscarriage. It is not feasible to detect the condition early as the mother may not show any symptoms. A simple blood test can reveal if you suffer from antiphospholipid syndrome and other similar conditions by testing antinuclear antibodies and antithyroid antibodies. If you suffer from this condition, then the treatment is taking aspirin and other blood thinning injections/medications so that the blood supply to the embryo is smooth and unhindered.
3. Hormonal and blood disorders: If the mother suffers from any hormonal conditions such as PCOS, thyroid or prolactin problems, then the risk of having a recurrent miscarriage is high. Also, suffering from a group of blood disorders, which are classified as thrombophilia also ups the risk of miscarriage as it leads to clot formation hindering the growth of the fetus.
4. Physical problems: Yes, structural abnormalities of the uterus such as fibroids can also lead to recurrent miscarriages. Cervical incompetence, a condition when the neck of the womb is loose, can make carrying a baby to the end of pregnancy more difficult. Another physical problem that can increase the risk of miscarriage is a condition in which the embryo gets stuck to the septum present inside the womb. If this happens, then the blood supply to the baby can be hindered leading to miscarriage.
In around 15% of the cases, there is no known cause of recurrent miscarriage, meaning everything is normal, but the couple can’t conceive. In such a case, the couple should go for a medical advice and give some time for the things to work out.