A single miscarriage can be a devastating event for expectant parents, and multiple miscarriages can be increasingly traumatic. When a woman has multiple miscarriages, it often indicates an underlying problem that will require diagnosis and treatment before she can have a successful pregnancy. Some of the most common underlying causes of multiple miscarriages include chromosomal, hormonal or uterine abnormalities. Additional possible causes include immunological issues, illness or exposure to environmental toxins.
The most common cause of miscarriages occurring in the first trimester is the presence of chromosomal or genetic abnormalities. These abnormalities interfere with the development of the embryo and could be present in either the mother’s chromosomes or the father’s chromosomes. The risk of these abnormalities increases for women older than 35. If a couple experiences multiple miscarriages because of chromosomal abnormalities, the couple might consider visiting a genetic counselor for guidance.
A hormonal imbalance referred to as luteal phase defect can lead to multiple miscarriages for some women. With this problem, a woman’s body does not create enough progesterone to sustain a successful pregnancy. Other issues with the thyroid or adrenal glands can affect a woman’s hormone levels and possibly can lead to miscarriage. Some women might benefit from hormone therapy as directed by a physician.
Structural abnormalities in the uterus also can lead to repeated miscarriages. In some cases, a miscarriage might occur because of the size, shape or formation of the uterus. If a woman has uterine fibroids, or growths, she also could have difficulty sustaining a pregnancy. For some women, these issues can be addressed with surgery.
Some immunological issues can keep a pregnancy from progressing. In some cases, the woman’s immune system views the developing embryo as a foreign object and attacks it. This might occur if the parents’ genetic material is too similar. Couples who experience multiple miscarriages often are encouraged to undergo immunological testing.
Women with chronic health conditions, including diabetes, heart disease or high blood pressure could experience repeated miscarriages if their health is not under control. Untreated infections, such as rubella or herpes, also can lead to problems sustaining a pregnancy. Women with health conditions should work with their doctors to manage the conditions in order to help prevent recurrent miscarriages.
Exposure to environmental toxins also can lead to miscarriage. This includes chemicals, radiation or substances such as alcohol, tobacco or drugs. Expectant mothers should limit their exposure to any of these toxins.
If a woman experiences multiple miscarriages, she should work with her doctor to determine the underlying cause and make a plan for treatment, if possible. She might be able to lower her risk of another pregnancy loss. Many women recover from miscarriages and go on to sustain successful pregnancies.