3D Ultrasound is a technical development of conventional ultrasound used for the spatial imaging of structures that are computed from a volume data record. (by recording a sonographic volume).

Using the so-called surface mode, it is possible to show the baby’s face in plastic form. (“Babyfacing”) It is also possible to use the recorded volumes to analyse organs, e.g. the brain, in layers like a computer tomogram. With the help of this technology, valuable additional information can be gained in case of certain childhood disorders.

(The ultrasound device uses this volume sonography to create three-dimensional images, which, for example, show the baby’s face (“babyfacing”). Other structures can also be shown in plastic form by means of 3D sonography. 3D ultrasound is therefore used in case of specific issues in order to gain additional diagnostic information.)

In the case of 4D ultrasound the timescale is added to the information from the 3D ultrasound as a fourth dimension. The examined structures are not only shown three-dimensionally, but the ultrasound data is recorded in “real time”, processed and reproduced in a rapid sequence of images (can even be viewed in motion.) 4D ultrasound thus makes it possible to show the movements of the extremities.

3D/4D sonography should only be seen as an enhancement of standard sonography, however, and is unable to replace it.

Synonym: 4D sonography

The PraenaTest® is a non-invasive prenatal diagnostic method (NIPT, non-invasive prenatal test) only for pregnant women who are in the 12th week of pregnancy or later and who have an increased risk of trisomy 21, 18 or 13 in the unborn baby.

Since 2012 it has been possible to analyse the fetal DNA by taking a blood sample from the mother and to rule out or diagnose trisomy 21,18 and 13 in the unborn baby with a high degree of probability. The definitive confirmation of the diagnosis is currently only possible by doing a subsequent amniotic fluid test (amniocentesis).

You can find more detailed information under: Blood test T21/18/13

Chorion is the name for the membrane surrounding the embryo in early pregnancy, which is called the placenta later on in pregnancy. It is formed by the embryo and is responsible for the exchange of substances between the mother and baby using finger-shaped protrusions(“chorionic villi”). The cells in the chorion are genetically identical to the cells in the embryo as a rule.

By means of chorionic villus sampling it is possible to remove tissue and to thereby examine the baby’s genetic makeup at a very early stage during the 11th – 13th week of pregnancy. A karyogram is prepared in this respect, whereby the chromosomes are counted and their structure examined. In case of specific issues, certain genetic disorders can also be ruled out.

Chorionic villus sampling is used as a preference in case of the following indications:

• an early suspicion of a deformity in the baby
• a significantly increased risk in first trimester screening
• to specifically rule out hereditary and metabolic disorders
• if the mother/parents request an early diagnosis.

Synonym: placenta tissue biopsy

During pregnancy, Doppler sonography provides a very good non-invasive examination method for determining the blood flow conditions and hence the supply situation in the mother’s and baby’s vessels. In this respect, ultrasound waves are used to show the direction and speed of the flowing blood and to therefore assess the blood flow between the womb and placenta (uteroplacental) and the foetus and placenta (fetoplacental).

Circulatory disorders and a lack of oxygen and nutrients, for example in case of retarded growth (IUGR – growth restriction – retardation) can therefore be studied to rule out or detect a placenta insufficiency.

With the aid of colour Doppler ultrasound, the flowing blood is made visible using colour coding, thus depicting the course of vessels and direction of blood flow, which is of major importance above all in fetal cardiac examinations.

Synonym: Doppler, Duplex, Power Doppler

Langdon Haydon Down (1828-1896) described a syndrome in 1866, whose carriers, due to their rounded face and slanted eyelids, resemble Mongolians, which led to the name “Mongolism”. This term is no longer used, however. Today we talk of Down’s syndrome, both in scientific literature and colloquial language.

Down’ syndrome is a genetic disorder where the set of chromosomes is modified. Instead of the usual 23 pairs of chromosomes, the cells of people with Down’s syndrome have an extra chromosome. Due to a problem during cell division, they have a third copy of chromosome 21 (“Trisomy 21”). Although the exact cause of the cell division failure is still unknown to this day, we do know that this risk of this increases the older the mother is.

Characteristic for people with Down’s syndrome, besides the external features, are a variable intellectual disability as well as the high occurrence of organ malformations. The disorder is not curable, yet the prognosis for people affected has significantly improved in recent years due to intensive treatment and funding opportunities.

Down’s syndrome can only be reliably ruled out prenatally by invasive diagnostics. Using prenatal medicine (nuchal translucency scan and organ ultrasound), the risk of the presence of Down’s syndrome can be limited, however.

Synonym: Trisomy 21

Edwards’ syndrom involves a chromosomal defect. Instead of the usual 23 pairs of chromosomes, the cells of people with Edwards’ syndrome have an extra chromosome. Due to a problem during cell division, they have a third copy instead of the usual two copies of chromosome 18 (“Trisomy 18”).

This is a serious development disorder, which leads to severe underweight and various organ malformations in the unborn baby, with the result that the foetus often dies in the womb. Children born with trisomy 18 usually die within the first few weeks.

Using prenatal diagnostics (first trimester screening, malformation ultrasound), signs of trisomy 18 can be detected. In order to back up the diagnosis, an invasive diagnostics procedure is necessary for genetic screening purposes.

Synonym: Trisomy 18

Puncturing the amniotic sac (amniotic cavity) guided by ultrasound to retrieve fetal cells in the amniotic fluid is called amniocentesis. This is possible from the 15th week of pregnancy and ideally in week 16/17 of pregnancy.

After cultivation (reproduction) and subsequent analysis of the fetal cells by preparing a karyogram, chromosomal defects (e.g. Down’s syndrome) can be ruled out with almost 100 % certainty. Using the FISH technique (fluorescence in situ hybridisation), deviations in the normal number of chromosomes can be detected within 24 hours.

In case of specific issues (e.g. familial genetic diseases or unusual ultrasound findings), under certain conditions these can be clarified by means of DNA analysis. By analysing the alpha fetoprotein, so-called neural tube defects (spina bifida) can be ruled out with a high degree of certainty.

Synonym: amniocentesis, amniotic fluid puncture

Human genetics is a branch of genetics that is concerned with the inheritance of genetic traits in people. Besides advising patients and providing medical diagnostics of certain genetic disorders, human genetics is devoted to researching the molecular biological causes of illnesses and developmental abnormalities.

Synonym: Medical genetics

The karyogram depicts all the chromosomes contained in a cell. The chromosomes photographed by a microscope are sorted at this stage according to morphological criteria. A normal karyogram includes 46 chromosomes (46 XX or 46 XY), which are arranged in pairs.

Synonym: chromosomal analysis

Nuchal translucency involves a collection of fluid between the skin and soft tissue at the back of the baby’s head, which can normally be seen between 11+0 and 13+6 weeks of pregnancy. Combined with the mother’s age and, if need be, two biochemical laboratory parameters(PAPP-A and ß-HCG), an individual risk of a chromosomal defect can be calculated.

Synonym: Nuchal fold, nuchal translucency

In the case of nuchal edema, there is a swollen collection of fluid at the back of the baby’s head (= NT > 95th percentile) A dorsonuchal edema is primarily seen as an indication of a chromosomal defect (e.g. Down’s syndrome). A nuchal edema can also be found more often than not, however, in babies with a heart defect and a number of other disorders described in literature (e.g. skeletal abnormalities and metabolic defects).

Synonym: dorsonuchal edema

Patau’s syndrome involves a characteristic malformation complex based on an extra copy of chromosome 13 (Trisomy 13). Apart from developmental abnormalities in various organ systems (brain, heart, extremities, kidneys, etc.), very severe developmental defects are found. Most babies born alive die within the first few months.

Synonym: Trisomy 13

Prenatal diagnostics covers all antenatal examinations of the expectant mother and unborn baby (embryo/foetus). The aim is to objectivise the fears and concerns of the expectant mother and to allay them if need be. Defects in the embryonic or fetal development should be detected in good time in order to enable optimal treatment.

In conflict situations, the doctor specialising in prenatal medicine, together with colleagues from other disciplines and counselling services, are on hand to give the parents sufficient information about all aspects of the disorder and its consequences for the parents and child.

Synonym: Prenatal diagnostics, prenatal medicine