Ultrasound screening study. Screening test for pregnancy

When a woman is waiting for a child, she has to take multiple tests and undergo the prescribed examinations. Each future mother can be given different recommendations. The same for all is a screening study. It is about him that will be discussed in this article.

Screening study

This analysis is assigned to all future mothers, regardless of age and social status. Screening study is carried out three times for the entire pregnancy. At the same time, it is necessary to observe certain periods for the delivery of tests.

Medicine knows screening methods of research, which are divided into two types. The first of these is a blood test from a vein. It determines the possibility of various pathologies in the fetus. The second analysis is an ultrasound screening study. When evaluating, the results of both methods must be taken into account.

What diseases does the analysis reveal?

Screening during pregnancy is not an accurate way of diagnosing. This analysis can only reveal the predisposition and establish the percentage of risk. To obtain a more detailed result, a fetal screening test should be performed. It is prescribed only if the risks of a possible pathology are very high. So, this analysis can reveal the possibility of the following diseases:

• Syndromes of Down and Edwards.
• Syndrome Cornelia and Patau.
• Syndrome Smith-Lemli-Opitsa.
• Possible defects or abnormal development of the neural tube.

When is the analysis assigned?

As already mentioned, a screening test is performed three times during pregnancy. In this case, the blood test is done only twice. There are certain dates in which it is necessary to undergo a survey.

Screening for the first trimester is scheduled from the eleventh to the fourteenth week of fetal development. The second examination must be completed on time from the twentieth to the twenty-second week. The third ultrasound screening test should be performed from the thirty-second to the thirty-fourth week of pregnancy.

Any departure from the deadline may give a false result. That is why it is better not to shift the dates of tests on your own, but to trust the doctor to conduct the calculations.

First examination

The most exciting moment for a future mother is the first protocol of a screening ultrasound and the result of a blood test. It should be noted that before this, no additional ultrasound is prescribed in the norm. This means that the woman first sees the baby on the screen of the device.

Blood test

As already noted, the first examination period can be conducted during the period from 11 to 14 weeks of pregnancy, but it is preferable to conduct this analysis from 12 to 13. First, the woman will have to donate blood. The analysis is performed strictly on an empty stomach. The material is taken from the vein. Previously, the future mother fills out the questionnaire, which indicates her age, the features of the course of pregnancy and previous birth (if any).

Further, the laboratory assistant examines the material obtained and notes possible malformations of the fetus. After that, the computer processes all received data and outputs the final result. It is worth noting that for different ages, the risks can be very different.

Ultrasound diagnostics

After giving blood to a woman, you need to undergo ultrasound. The procedure can be performed in two ways: by the vaginal sensor or through the abdominal wall. Everything depends on the apparatus of ultrasound, the qualification of the doctor and the period of pregnancy.

During the examination, the doctor measures the growth of the fetus, notes the peculiarities of the location of the placenta. Also, the doctor must make sure that the child has all the limbs. One of the important items is the presence of the nasal bone and the thickness of the collar space. It is to these points that the doctor will subsequently rely on deciphering the result.

The second survey

A screening test for pregnancy in this case is also conducted in two ways. First, a woman needs to take a blood test from a vein and only after that go through ultrasound. It is worth noting that the established time limits for this diagnosis are somewhat different.

Blood test for second screening

In some regions, the country does not conduct this study at all. The exception is made only by those women whose first analysis gave disappointing results. In this case, the most favorable time for blood donation is in the range of 16 to 18 weeks of fetal development.

The test is the same as in the first case. The data is processed by the computer and outputs the result.

Ultrasound examination

This examination is recommended for a period of 20 to 22 weeks. It is worth noting that, unlike the blood test, this study is conducted in all medical institutions of the country. At this stage, the height and weight of the fetus are measured. Also, the doctor examines the organs: the heart, the brain, the stomach of the baby's future. The specialist counts the fingers on the hands and feet of the crumbs. It is also very important to note the condition of the placenta and cervix. In addition, doplerography can be performed. During this examination, the doctor monitors the blood flow and notes possible defects.

During the second ultrasonic screening, it is necessary to inspect the water. They should be a normal amount for a given period. Inside the membranes there should be no suspensions and impurities.

The third survey

This type of diagnosis is carried out after 30 weeks of pregnancy. The most suitable time frame is 32-34 weeks. It is worth noting that at this stage, the blood is no longer being screened for defects, but only by ultrasound.

During the manipulation, the doctor carefully examines the organs of the future baby and notes their features. The height and weight of the crumb are also measured. An important point is normal motor activity during the study. The specialist notes the amount of amniotic fluid and its purity. Mandatory in the protocol indicates the condition, location and maturity of the placenta.

This ultrasound is in most cases the last. Only in some cases, before the birth, repeated diagnostics is prescribed. That is why it is so important to note the position of the fetus (head or pelvic) and the absence of a cord with the umbilical cord.

Deviations from norms

If during the examination various deviations and errors were revealed, the doctor recommends that genetics appear. At the admission specialist must take into account all the data (ultrasound, blood and especially pregnancy) when setting a certain diagnosis.

In most cases, possible risks are not a guarantee that the child will be born sick. Often, such studies are erroneous, but despite this, doctors can recommend additional studies.

A more detailed analysis is a screening study of the microflora of the amniotic fluid or blood from the umbilical cord. It is worth noting that this analysis entails negative consequences. Quite often after such a study there is a threat of termination of pregnancy. Every woman has the right to refuse such a diagnosis, but in this case, all responsibility falls on her shoulders. When confirming the poor results, doctors suggest an artificial termination of pregnancy and give the woman time to make a decision.

Conclusion

Screening during pregnancy is a very important analysis. However, we must not forget that it is not always accurate.

After the birth, the child will undergo neonatal screening, which will absolutely accurately show the presence or absence of any disease.