Missed abortion. Causes, Symptoms, Prevention

A missed abortion refers to a complex of symptoms including intrauterine fetal death, pathological myometrium inertness and hemostasis disorders.

Missed abortion Causes, Symptoms, Prevention

Other synonyms for a missed abortion are a missed miscarriage and an early fetal demise.

Most often a missed abortion happens during the first trimester of pregnancy. Here are the most vulnerable periods:

  • 7th — 12th days of pregnancy (period of implantation);
  • 3rd to 8th week of pregnancy (embryogenesis);
  • the first 12 weeks (placenta formation);
  • 20th — 24th weeks of development (the formation of the most important body functions).

During these periods the fetus is most sensitive to the damaging and destructive factors.

Missed abortion causes

The causes for an early fetal demise are numerous and often complex. Unfortunately, it’s often impossible to establish one specific factor that has led to this pathology. Maceration of tissues that occurs after fetal death (moist aseptic necrosis) complicates both genetic and morphological studies of possible missed abortion causes.

Among the most common reasons are:

  • hormonal disorders in a female body.

Such malfunctions can cause a deficiency of progesterone or estrogen imbalance, which do not allow the fetus to obtain sufficient nutrients. This leads to the termination of the development and subsequent fetal death. Usually this happens in the first trimester of pregnancy.

Hormonal disorders can be diagnosed before pregnancy. They appear as a result of ovarian dysfunction, thyroid disease, endocrine diseases, polycystic ovary syndrome. Therefore, it is important to undergo examination in the pre-pregnancy period.

  • Immunological factors.

Sometimes the mother’s organism sees the fertilized egg as a foreign body, due to the fact that the egg contains about 50% of the father’s genetic information.

In response, the mother’s body protective functions activate and produce antibodies aggressive to the embryo. In fact, the immune system kills the fetus.

  • Antiphospholipid syndrome (APS).

APS is a group of autoimmune disorders when a woman has a significant amount of antibodies to phospholipids in blood plasma. APS is the reason for almost 5% of all miscarriages. AFS is also diagnosed in 27−42% of all cases of repeated miscarriages. Genetic predisposition is the main cause for the syndrome.

Antiphospholipid syndrome often leads to thrombosis. Most often thrombosis is formed in the deep veins of the leg, as well as in renal and hepatic veins.

The risk of thrombosis increases during pregnancy. Therefore, it’s better to diagnose APS and to have an appropriate treatment before pregnancy. If APS is diagnosed during pregnancy, the prospective mother needs constant monitoring and adequate treatment, preferably in hospital. Antiphospholipid syndrome can have a negative impact on the course of childbirth and the postpartum period.

  • chromosomal abnormalities,

The death of the embryo is sometimes caused by negative structural changes in the genetic program. A genetic defect can be inherited by the embryo from the mother or father. And can also occur because of abnormal combination of genes of both parents. If chromosomal abnormalities were the reason for an early fetal demise, the couple must undergo genetic testing before planning the next pregnancy. Unfortunately, it’s not possible to prevent an abnormal combination of genes. Sometimes, the problem can be solved through the use of donor genetic material instead of the genetic material of one of the parents.

  • acute or chronic infectious diseases,

The most typical diseases resulting in a missed abortion are chlamydia, herpes (cytomegalovirus), toxoplasmosis, mycoplasmosis, ureaplasmosis etc. These infections might have been living in the female body for a long time before pregnancy. However, pregnancy weakens the immune system and allows the infections to become stronger and more destructive.

Cytomegalovirus is a frequent cause for embryo death. This infection can also result in the development of birth defects and serious illnesses of the baby.

Gonorrhea and syphilis are undoubtedly dangerous threats. Even flu accompanied with high temperature and other adverse factors can provoke a missed abortion. Pneumonia, pyelonephritis and other diseases can also be dangerous without proper treatment.

Rubella and missed abortion.

Any contact with people with rubella may cost a pregnant woman the life of her developing fetus. Rubella is the biggest threat for the embryo’s life and health. When infection occurs in the first trimester, medical abortion is strongly recommended. The threat significantly reduces after the 16th week of fetal development.

In 10−40% of cases, women with rubella have a spontaneous miscarriage in the early stages of pregnancy. If the baby was born, in 10−25% of cases he dies from birth defects in the first year of life. Analysis of immunity to rubella virus should be done before conception. If a woman has not had rubella, she should have vaccination before a planned pregnancy.

  • External factors.

Unfortunately, such trivial things as climate changes, sudden changes of atmospheric temperature, prolonged flights, lifting heavy things, exposure to radiation, staying long in the sun and even tanning booths can cause early fetal demise.

  • Addictions: drugs, alcohol, smoking.

A most paradoxical and common cause for missed miscarriages is drinking alcohol while pregnant.

  • Causes of unknown origin.

As it was already mentioned, the reasons for a missed abortion pathology are not fully understood. In some cases, they are impossible to identify. Superstitious people prefer to believe that the child just wasn’t meant to be born.

All possible risk factors must be eliminated at the planning stage or in early pregnancy.

Symptoms of a missed miscarriage.

A pregnant woman may suspect that something went wrong with her pregnancy if

  • her symptoms of toxicosis suddenly stopped;
  • she feels lower abdominal pain;
  • her mammary glands became less elastic;
  • her basal temperature (measured in the rectum) decreased;
  • her body temperature — on the contrary — increased;
  • she feels deterioration, weakness, chills;
  • she has no more pregnancy signs.

If you suspect a missed abortion — first of all, you need to seek professional medical help. Sometimes, women with missed miscarriages have no symptoms at all. It is extremely dangerous, because the dead fertilized egg can cause the development of DIC (Disseminated Intravascular Coagulation). DIC is dangerous, as the blood loses its ability to clot and any bleeding can become fatal.

A missed abortion in early pregnancy can be diagnosed in 3 ways.

  1. A blood test for the HCG hormone will show that HCG level is lower than normal.
  2. During a gynecological examination a doctor can determine the inconsistency of uterine size and gestational age.
  3. During an ultrasound examination the doctor will determine the lack of a heartbeat.

How to prevent a missed abortion?

What to do after a missed abortion to avoid its repetition?

To exclude this diagnosis in future, therapeutic interventions begin with a full examination of both partners, including:

  • vaginal smear;
  • ultrasound examination of pelvis organs;
  • smear for hidden infections: herpes, HPV, cytomegalovirus, chlamydia and other STI pathogens;
  • study of the karyotype of the mother and father;
  • sperm analysis;
  • a blood test for hormone levels: estradiol, progesterone, FSH, prolactin, DHEA, etc.;
  • a blood test for levels of thyroid hormones;
  • an analysis of the presence of infections (TORHC-complex);

If you already had a missed miscarriage, the doctors must also do

  • a histological examination of the contents of the uterus;
  • a cytological and genetic study of the dead fetus (in order to detect any genetic abnormalities).

Further treatment is aimed at:

  • the elimination of the causes of missed abortion;
  • strengthening the immune system;
  • the stabilization of your menstrual cycle.

Doctors recommend to plan the next pregnancy not earlier than 6−8 months after the treatment.