Prenatal Diagnostics: Treatment, Effects & Risks

The term prenatal diagnostics covers various examinations that take place during pregnancy. They deal with the early detection of diseases and maldevelopments of the unborn child.

What is prenatal diagnostics?

The term prenatal diagnostics covers various examinations that take place during pregnancy. Prenatal diagnostics (PND) refers to medical examination procedures and devices that deal with the early detection of diseases and malformations of the unborn child. Prenatal diagnostics allows therapeutic countermeasures to be taken at an early stage. This may involve surgical intervention or even termination of the pregnancy, depending on the extent of the malformation or disease. The term prenatal translated from Latin means “before birth”. Thus, prenatal examinations are used exclusively before birth and especially in the last two trimesters of pregnancy. Prenatal diagnostics can usually be performed from the end of the third month of pregnancy.

Treatments and therapies

Prenatal diagnostics is used to rule out or reliably detect abnormal developments in the unborn child. These are primarily malformations that have a genetic background and often mean severe disabilities for the affected child. The results of prenatal diagnostics make it possible to identify certain genetic abnormalities such as rare hereditary diseases or diseases of the metabolism, blood and muscles. These include trisomy 21 (Down syndrome), Huntington’s disease, Duchenne-type muscular dystrophy, and cystic fibrosis. However, successful therapy of most diseases during pregnancy or after the birth of the child is possible only in rare cases. In addition, prenatal tests cannot indicate the exact severity of the disability. Furthermore, only about five percent of all disabilities are congenital. Most of them only develop later in life due to illnesses. However, certain factors may make it advisable to have prenatal diagnostics performed by a specialist. These are diseases of the mother, which include epilepsy, infections during pregnancy, genetic diseases within the family, and the occurrence of malformations in a previous pregnancy. Other possible reasons include abnormal or unclear ultrasound findings during a gynecological examination, an already established malformation, the desire for an amniocentesis, or the presence of a multiple pregnancy. With its examination methods, prenatal diagnostics supplements the conventional procedures that routinely take place during pregnancy. The costs of prenatal procedures are usually only covered by health insurance companies in special cases, such as the existence of certain hereditary diseases. In some cases, performing prenatal diagnostics can cause severe stress for the parents. For example, important questions arise about further examinations and possible risks, as well as about the effects on future life in the event of a disability of the child. Likewise, the termination of the pregnancy may be discussed. These questions often cause psychological problems for the parents. For this reason, the performance of prenatal diagnostics should be well weighed in advance and discussed in detail with the doctor.

Diagnosis and examination methods

In prenatal diagnostics, it is important to distinguish between non-invasive and invasive examination methods. The term non-invasive means that the examination instruments do not penetrate the organism of the pregnant woman. There are no risks for either the mother or the unborn child. In contrast, invasive procedures involve penetration of the pregnant woman’s body, which sometimes leads to certain risks. Among the most commonly performed non-invasive prenatal procedures is ultrasound examination (sonography). Examinations with ultrasound basically take place two to four times during pregnancy. There may also be additional special sonographies such as nuchal fold measurement. Ultrasound examinations are considered to be just as risk-free as special blood tests.These include measuring blood pressure, CTG monitoring and determining iron levels. These measures are standard procedures. If an invasive examination method is performed, this means an intervention in the body of the mother and child. One of the most common invasive procedures is amniocentesis. Amniotic fluid is removed through the abdominal wall of the pregnant woman under ultrasound observation. The amniotic fluid contains cells of the child that provide information about possible disorders. The doctors look for any deviation from the usual number of chromosomes. Another invasive procedure is chorionic villus sampling, which involves the removal of placenta. This examination is performed, among other things, to exclude Down syndrome. The same applies to umbilical cord puncture. In this method, the gynecologist takes umbilical cord blood from the child in order to examine the blood cells it contains. Anesthesia is not necessary for either examination procedure, which can be compared to a blood draw. The diagnostic procedure is always performed on an outpatient basis. Preimplantation diagnostics is a special case within prenatal examination methods. Here, examinations are performed on embryos that are a few days old and were created in the course of artificial insemination. The examination takes place before the embryo is transferred to the uterus. With this procedure, possible changes in the chromosomes can be detected in time. This includes, for example, a change in the number of chromosomes. In addition, changes in individual genes can be detected. Although the invasive methods of prenatal diagnostics provide valuable information, they also harbor some dangers. For example, a miscarriage may well occur. However, the risk is considered relatively low.