Genetic ultrasound between weeks 11 and 14 of pregnancy should be performed before the end of the 13th week and the 6th day of pregnancy. The condition is also the appropriate parietal-seated length of the fetus - it must be between 45 and 84 mm. This test is colloquially called "genetic ultrasound" and should be performed in every pregnancy. They are performed with a transabdominal head, and only in the case of significant obesity - transvaginal.
Genetic ultrasound between 11 and 14 weeks of pregnancyis reimbursed if the referral is issued by a doctor who has a contract with the National He alth Fund (costs about PLN 250 without reimbursement).
The aim of the test is to initially assess all the organs of the fetus, to assess the risk of developing the most common diseases in the fetus resulting from chromosomal defects (Down's, Edwards and Patau's syndromes) and to assess the gestational age. Each abnormality or doubt should be an indication for fetal examination at the reference center.
ImportantPregnant ultrasound: glossary of abbreviations
CR L - parietal length FHR - fetal heart rate NT - nuchal fold translucency NB - nasal bone DV - venous flow BPD - transverse dimension of the head HC - head circumference AC - belly circumference FL - femoral length EFW - estimated fetal weight
Which pregnancy tests are mandatory?
What exactly is rated?
- age of pregnancy - during this period it can be assessed with an accuracy of 7-10 days. This is important if you have irregular periods as the age of your last period is not accurate
- external and anatomical structure of the fetus - the head, torso, lower and upper limbs are examined, the parietal-seat length (CRL) is measured, i.e. the length of the child from the top of the head to the buttocks. Internal organs are also assessed: the brain, stomach, bladder, spine and heart. The assessment of the heart includes its structure, location and beating rate (FHR). During this period of pregnancy, the FHR is usually 150-170 beats per minute.
- a parameter that may indicate an increased risk of the most common chromosomal aberrations is the so-called the translucency of the nape fold (NT). It is a reservoir of fluid in the nape of the neck that is found in every child during this stage of development. Usually
- the width of this reservoir is 1-3 mm,a large amount of fluid (over 2.5 mm) may or may not indicate an illness.
A particularly clear relationship was found here with Down's syndrome, but there is also a relationship with, for example, diseases of the heart and other organs.
Sometimes the following are also rated:
- presence of the nasal bone (NB) - its absence is typical for children with Down syndrome
- blood flow in the venous duct (DV);
- the venous duct is a unique vessel that only occurs in utero: it connects the umbilical vein with the vein that leads blood to the heart, abnormal flow in this vessel is characteristic of children with heart defects and genetic syndromes (Down, Edwards and Patau) .
What do the results say?
The results of the study only determine the statistical probability of the already mentioned diseases based on the mother's age. There are statistics based on how many women of a given age give birth to a child with Down's disease, e.g. for 32 years the risk is 1: 447, i.e. one in 447 women at this age will give birth to a sick child. A score of 1: 100 is an increased risk, but still means that out of a group of 100 women, only one will give birth to the affected child. If the result is 1: 2,233, it means that in a group of 2,233 women, only one would have a sick child, so the risk is very small. However, this test can never be 100% sure that your baby will be completely he althy.