Prenatal diagnostics months 4 to 6 | Sanitas magazine

Is my unborn child healthy? What tests are available now?

Prenatal diagnostics are quick and indicate whether your baby is healthy – but they are not 100% accurate. They merely calculate the risk of health problems and many couples prefer to do without. No one is obliged to undergo these tests; you have the right not to know. The vast majority of babies are born healthy; only 2% to 4% are born with a birth defect.

Definition of prenatal diagnostics: Not all prenatal examinations are defined as prenatal diagnostics in the strictest sense of the term. For instance, testing for antibodies in the mother’s blood or regular urine tests do not come under this umbrella term. Prenatal diagnostics refer instead to the identification of specific hereditary diseases such as chromosomal abnormalities (Down’s syndrome is the most common) or rare single gene disorders known to be present in the family.

Reliability and risk of tests: There are not (yet) any prenatal tests that can detect the wide range of congenital disorders, chromosomal abnormalities and genetic defects with 100% accuracy and no associated risk (e.g. mscarriage). Furthermore, in the majority of cases, prenatal diagnostics can’t make a prognosis on the severity and individual characteristics of any potential disability. Very often, the pregnant woman is under pressure to decide quickly whether to terminate the pregnancy or not.

Non-invasive tests in the second trimester:

  • Regular ultrasound scans
  • Analysis of mother’s blood (serum screening) from 14th to 20th week
  • Obstetric ultrasonography between the 19th and 22nd/23rd weeks: The organs of the foetus are so well-developed now that diseases or abnormalities can be identified. If you know before the birth that your child will need special treatment, you can get in touch with the appropriate specialists now. It also means the birth itself can be better planned. For example, if a normal birth is too high risk for a child with a heart defect, a caesarean section can be organised. If necessary, the newborn child can be treated with medicines or operated on directly afterwards.


Invasive tests in the second trimester:

  • Tissue taken from the placenta (placental biopsy) from the 12th week onwards
  • Amniocentesis from the 13th week onwards
  • Blood drawn from the umbilical cord (cordocentesis) from the 18th week onwards