Causes of non-pregnancy: genetic, endocrine

The issue of miscarriage is one of the most pressing in modern obstetrics. Today, the number of spontaneous interruptions is approximately 10-25%, with 50% of cases occurring in the first trimester, about 20% in the second trimester, and 30% in the third trimester. The causes of miscarriage, as well as the factors, can be numerous and varied. It is important to know about them, as this can help prevent possible complications and take measures in advance.

The causes of miscarriage are extremely varied and depend on many factors.

There is currently no comprehensive classification of the causes of miscarriage. Apparently, this is due to the fact that it is difficult to reduce all the variety of reasons leading to termination of pregnancy into a single system. Spontaneous miscarriage is often the result of not one, but several reasons acting simultaneously or sequentially.

Currently, the following leading causes of habitual pregnancy loss are distinguished:

1. genetic;
2. endocrine;
3. immunological (autoimmune, alloimmune);
4. infectious;
5. thrombophilic;
6. uterine pathology (malformations, genital infantilism, uterine hypoplasia, isthmic-cervical insufficiency, intrauterine adhesions).

Finding out the causes of habitual pregnancy loss is extremely important from a practical point of view. Knowing the causes and understanding the pathogenesis of pregnancy loss, one can more successfully carry out pathogenetic treatment, otherwise it becomes symptomatic and often ineffective.

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Genetic causes

In about one in ten cases, the process of bearing a child is interrupted due to chromosomal abnormalities in the fetus. In other words, the fetus has genetic abnormalities that threaten the viability of the child after birth. The body reacts to the presence of such abnormalities by spontaneously terminating the pregnancy - in a way, this can be called natural selection.

Genetic disorders and associated spontaneous abortions often occur in women who have a history of miscarriages, birth defects in children, and other disorders in their families.

Quite useful information about the presence of anomalies can be obtained by examining the cytogenetics of the fertilized egg removed after a spontaneous abortion. And in order to determine whether genetics was the main factor in the miscarriage, it is necessary to examine the karyotype of the planning couple. If the doctor finds a discrepancy in the karyotype, then such a couple is recommended to consult a geneticist. Even an abnormal karyotype of only one of the parents increases the risk of developing genetic disorders many times over. In such cases, the doctor advises to undergo perinatal examinations, which include chorion biopsy, amniocentesis, and cord blood examination (cordocentesis).

Endocrine factors

Other most common causes of miscarriage include endocrine disorders, such as insufficient luteal phase, excessive androgen or prolactin levels, thyroid disease, and diabetes. These disorders cause spontaneous miscarriage in the first trimester of pregnancy in a quarter of a percent of cases.

An insufficient luteal phase occurs when there is a small amount of progesterone, which maintains and supports the process of gestation. Progesterone plays a special role at the beginning of pregnancy - during the attachment of the fertilized egg to the walls of the uterus. Due to an insufficient amount of the hormone, the embryo may not attach, or attach poorly, which will lead to an interruption of the process.

To maintain the amount of progesterone in the body, drugs such as Utrozhestan, Progesterone, Injesta, Duphaston can be prescribed. With a simultaneous deficiency of progesterone and an excess of androgens, Methylprednisolone is taken.

Excess androgens themselves can also provoke miscarriage, which can be the result of increased production of testosterone, which is produced in the adrenal glands and ovaries. This can happen with hereditary pathologies of the adrenal glands, with polycystic ovary disease, with a malfunction of the hypothalamus-pituitary ligament.

Increased prolactin levels – the next cause of endocrine miscarriage – can occur as a result of trauma, inflammation, neoplasms in the brain, or more precisely – in the hypothalamus-pituitary ligament. Sometimes this condition can be the result of taking certain medications (antidepressants, oral contraceptives).

Among thyroid pathologies, the most common causes of miscarriage are iodine deficiency in the body and thyroiditis. With such diseases and conditions, the thyroid gland is forced to produce fewer hormones, and, as a result, they are not enough to fully support pregnancy. If such conditions occur, the doctor will definitely prescribe treatment with thyroid hormones or medications containing iodine.

In diabetes, miscarriage may be associated with decreased susceptibility of the body's cells to insulin. Because of this, the doctor always reviews the insulin dosage in pregnant women with diabetes.

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Anatomical factors

An important factor that can lead to miscarriage are defects in the anatomy (structure) of the reproductive organs. First of all, these are defects in the structure of the uterus: double uterus, bicornuate, unicornuate or saddle-shaped uterus, intrauterine septum, etc. In addition, myomas and Asherman's syndrome (uterine synechiae) are also considered anatomical structure disorders.

ICI is a disorder of the locking function of the cervix, or isthmic-cervical insufficiency. This pathology is characterized by shortening of the cervix with its subsequent opening. Most often, this condition manifests itself in the second half of pregnancy. If the pathology is noticed in a timely manner, the woman undergoes cervical suturing.

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Infections as a cause of miscarriage

Diseases such as chlamydia, ureaplasma, mycoplasma, trichomonas, papilloma virus, herpes infection, cytomegalovirus can also worsen the course of pregnancy. According to statistics, more than 40% of miscarriages are associated with the negative effects of bacteria and viruses. Because of this, pregnant women who are diagnosed with the listed pathologies are prescribed treatment with immunoglobulins. The type of treatment is selected according to the type of pathogen.

Immunological factor of miscarriage

What do immunological causes include? They can be called almost any unpredictable reaction of the woman's immune defense to the supposedly foreign tissues of the future child (alloimmune disorders), or even to the patient's own tissues (autoimmune disorders). In case of immunological pathologies, a blood test is performed, where the presence of antibodies (antinuclear, antiphospholipid, antithyroid), or antibodies to chorionic gonadotropin are determined.

Treatment of immunological disorders is usually long-term, often until the birth itself.

The reasons for miscarriage are mostly serious. In such cases, you can't do without qualified, full-fledged diagnostics and treatment. But eliminating the underlying cause almost always leads to a positive result - a long-awaited pregnancy and the birth of a strong and healthy baby.