Indicators of second screening for pregnancy
The second screening for pregnancy is conducted to identify possible chromosomal abnormalities in the fetus. The second screening usually assigns a "triple test" - a blood test for the level of hormones:
- Estirol (produced by the placenta, low level indicates the pathology of the future child)
- AFP or alpha-fetoprotein (a protein that is present in the mother's blood only during pregnancy, with a decreased or increased level, the condition of the unborn child is disrupted, a sharp increase in protein indicates fetal death)
- HCG or human chorionic gonadotropin (begins to be produced in the first days of pregnancy, a lower level indicates a pathology in the development of the placenta, elevated - to chromosomal abnormalities, gestosis and some other pathologies).
If necessary, a determination is made of the level of inhibin A, a lower level of which indicates chromosomal pathologies (Down's syndrome, etc.).
The AFP level in Down syndrome decreases, and hCG increases.
With Edwards syndrome, there is a lowered level of hCG, the rest are within normal limits.
Elevated AFP indices may indicate abnormalities in the kidneys in the fetus, abdominal wall disorders.
It is worth noting that the syndrome of Edwards and Down through screening can be detected only in 70%. To avoid mistakes, the doctor must evaluate the results of the blood test together with the results of the ultrasound.
If the blood test is normal, then the doctor assesses the development of the child as normal. With minor deviations in one direction or another, one can not immediately assume pathology, since testing is often false, in addition, there are some factors that can affect the results (for example, in multiple pregnancies, diabetes, smoking, inaccurate timing, excessive pregnancy weight ).
Interrupt the pregnancy or make a diagnosis only relying on the results of screening, no doctor can. This testing provides an opportunity to assess the probability of congenital abnormalities in a child. If a woman's probability of having a child with pathologies is high, then she is assigned a number of additional studies.
Results of the second screening for pregnancy
The second screening during pregnancy can sometimes show poor results, but this is not an excuse to despair and panic ahead of time. The results of the screening may indicate a high probability that some anomalies are possible, but do not confirm this by 100%.
If the second screening showed a significant deviation from the norm of at least one of the indicators, the pregnant woman is assigned an additional examination.
Also, some factors may affect the results of screening testing:
- in vitro fertilization;
- excess weight during pregnancy;
- presence of chronic diseases (diabetes mellitus);
- harmful habits of the future mother (smoking, drinking, etc.).
It should be noted that if a woman is pregnant with twins (triplets, etc.), the biochemical blood test is considered inappropriate, since in this case the woman will have all the indicators above the norm and will not be able to calculate the developmental risks of development disorders.
The second screening during pregnancy allows a woman and her doctor to get information about the condition of the fetus, its development, and also about how the pregnancy goes. Doctors prescribe a screening study in the first two trimester, in the third trimester, screening is done only if necessary.
Carrying out such a survey should not cause fear in the pregnant woman, the overwhelming majority of women are positive about the screening.
It is recommended to do all screening studies during pregnancy in one laboratory, which will make it easier for the doctor to decipher the results.