During pregnancy, it is crucial to watch out for infections that could endanger the well-being of both mother and child.

Certain infections can have serious effects on the unborn child during pregnancy. However, modern medical tests offer the possibility of detecting these infections at an early stage and taking appropriate measures to minimise the risk of complications.

The most important tests include screening for toxoplasmosis, cytomegalovirus (CMV), varicella (chickenpox), parvovirus B19 and streptococcal swab.

Toxoplasmosis screening
Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. The pathogen can be transmitted through the consumption of raw or undercooked meat and through contact with cat faeces. Toxoplasmosis infection can have serious consequences for the unborn child, especially during pregnancy, particularly if the mother is infected for the first time during pregnancy.

Toxoplasmosis infection during pregnancy can lead to miscarriage, premature birth or serious developmental disorders in the child, especially if the infection occurs in the first trimester of pregnancy. In later weeks of pregnancy, the risk of damage is lower, but even then, visual impairment, mental disability or other health problems can occur.

Toxoplasmosis screening is carried out at the beginning of pregnancy. If you test negative for antibodies, regular check-ups are recommended to detect any possible infections during pregnancy at an early stage.

As a rule, screening is repeated every 4–6 weeks during pregnancy, especially in high-risk cases.

If toxoplasmosis infection is detected during pregnancy, immediate treatment is necessary to reduce the risk to the child. Treatment is usually with antibiotics.

CMV (cytomegalovirus) screening
Cytomegalovirus (CMV) is a herpes virus that usually causes no symptoms, but can pose a risk to the unborn child during pregnancy. If a pregnant woman becomes infected with CMV for the first time, the virus can be transmitted to the unborn child and cause serious damage such as malformations, mental disability or hearing loss. CMV screening is done through a blood test that shows whether you have already developed antibodies to the virus. If a CMV infection is detected, antiviral treatments and regular ultrasound examinations can help minimise the risk to the child. There is currently no specific vaccination available, which is why preventive measures such as good hygiene and avoiding contact with bodily fluids from small children are crucial to prevent infection.

Varicella (chickenpox) screening
Varicella is a highly contagious viral infection that occurs in childhood as chickenpox. If a pregnant woman has never had chickenpox or been vaccinated, there is a risk of infection during pregnancy.

A chickenpox infection during the first trimester of pregnancy can lead to severe malformations in the child, while an infection later in pregnancy increases the risk of premature birth or low birth weight.

A blood test can determine whether they are immune to the virus. Vaccination during pregnancy is not recommended.

Parvovirus B19 screening (fifth disease)
Parvovirus B19 is the pathogen that causes the so-called ‘third disease’ or ‘cheek disease’, which is common in children. However, infection during pregnancy, especially in the second trimester, can have serious effects on the unborn child, including anaemia and, in severe cases, even heart failure. The virus is mainly spread through airborne droplets and is particularly dangerous if you have had direct contact with infected children. A blood test can show whether you already have antibodies against parvovirus B19. If an infection is detected, ultrasound examinations and other diagnostic procedures can be used to monitor the well-being of the child.

β-streptococcus (GBS) swab
Group B beta streptococcus (GBS) are bacteria that are found in the vagina and rectum of many people without causing any symptoms. However, during childbirth, these bacteria can be transmitted to the child and cause serious illnesses such as pneumonia or blood poisoning. For this reason, a smear test for beta streptococci is recommended in the late stages of pregnancy (between the 35th and 37th week). The test is performed by taking a vaginal and rectal swab. If GBS is detected, antibiotic treatment is administered during childbirth to reduce the risk of transmission to the child.

Why are these screenings important?
These infection screenings offer crucial protection for the health of mother and child. They help to detect infections early on and, if necessary, treat them before they can have serious consequences. Some of the infections tested for can occur without symptoms, which is why regular testing is necessary.

These tests are not part of standard preventive medical check-ups.

NIPT Rh
NIPT Rh is a specific test that determines the Rh factor of the unborn child. The Rh factor is a protein that may be present on red blood cells. If a mother is Rh-negative and the child is Rh-positive, this can lead to Rh incompatibility.

In such cases, the mother’s immune system may develop antibodies against the child’s Rh-positive blood. These antibodies can lead to complications in later pregnancies, such as haemolytic disease of the newborn (HDN), in which the child develops anaemia or other health problems.

How does NIPT Rh work?
NIPT Rh tests the free foetal DNA in the mother’s blood for the Rh status of the child. The test can determine whether the child is Rh-positive or Rh-negative, so that measures can be taken early on to prevent Rh incompatibility if necessary.

If the test shows that the child is Rh-positive, treatment with anti-D immunoglobulin is usually recommended to prevent the mother from forming antibodies. This is typically carried out in the 28th week of pregnancy and after the child is born.