With the onset of pregnancy, each woman periodically visits the doctor, performs laboratory tests, undergo an ultrasound examination (screening 2 trimester), which allow to assess the condition of the fetus, to identify the slightest changes or pathologies of development. Throughout pregnancy, a woman should undergo three routine examinations. If you suspect a pathology, the presence in the history of women of chronic diseases, the number of ultrasound procedures may be increased. It is proved that ultrasound is a safe and informative research method that does not harm the fetus and does not affect the course of pregnancy. In the second trimester of pregnancy, the physician must prescribe screening, which provides a complex of research, including ultrasound diagnostics and laboratory tests of blood and urine. The diagnostic results help the doctor to determine the norms and possible complications, to recognize abnormalities or congenital abnormalities.
The second screening of pregnant women is carried out in the second trimester of the gestational period. It is mandatory, held on the 16th – 19th week. The main indicators to which the doctor draws attention are hCG (human chorionic gonadotropin), AFP (alpha-fetoprotein) and free estriol (E3), as well as the results of ultrasound. If pathology is suspected, a screening test may be prescribed to evaluate hormonal levels. Screening of the 2nd trimester should not frighten a pregnant woman, since it is a mandatory research method. If the pregnancy is uneventful, a complete diagnosis is not necessary, you can get by conducting an ultrasound diagnosis. In order to get acquainted with the screening in more detail, it is important to know when it is prescribed, what its norms and deviations are, and also how to properly prepare for the procedure in order to get the highest possible results.
Should pregnant women undergo a second screening
The main purpose of screening in the second trimester is to identify defects in the development of the fetus and identify possible risks for the future mother. This research method is assigned to confirm or refute various risks that were obtained during the initial diagnosis in the first trimester. Full screening is not given to all women, but only those in the risk group suffer from chronic pathologies or have a difficult time carrying a child. The main indications for diagnosis are the following conditions and diseases:
- age of the woman after 35 years;
- poor heredity;
- genetic diseases;
- viral diseases in the first trimester;
- miscarriages, fetal death, ectopic pregnancy in the past;
- conceiving a child by close relatives;
- dependence of parents on drugs, alcohol;
- taking drugs that are prohibited during pregnancy;
- autoimmune diseases;
- chronic diseases of internal organs and systems that can harm the fetus, affect its growth and development.
The indications for screening may be other diseases or conditions that may lead to the development of pathologies in the fetus. For the diagnosis, it is not necessary to have any health problems. If a woman wants to undergo screening to ensure the healthy development of the fetus, the doctor will give directions. The procedure is completely safe for both the woman and her unborn child.
What is looked at second trimester ultrasound
In the second trimester of pregnancy, the fetus is fully formed, so doctors, having on their hands the results of examinations, can easily determine whether there are abnormalities or pathologies in its development. The second screening examination allows the doctor to identify many pathologies of the fetus, including:
- brain or spinal cord defects;
- liver disease;
- anomalies of the digestive tract.
- facial cleft;
- heart defects;
- defects of the limbs, torso.
Anomalies and defects that can be detected at the 2nd screening are often not subject to correction, often act as an indication for abortion on medical grounds. In addition to pathologies, this research method determines the presence of markers of fetal chromosomal abnormalities, including:
- embryo development delay;
- much or shallow water;
- underdeveloped length of tubular bone;
- cysts of the vascular plexus of the brain or spinal cord.
Thanks to the results, it is possible to identify other pathologies in the development of the fetus. Carrying out ultrasound diagnostics also allows to obtain informative results on the development and growth of the fetus, to evaluate the norms and deviations:
- the structure of the face (size of the nasal bone, nose, ears, eyes);
- size, weight of the fetus;
- lung maturity;
- the structure of the brain, heart, blood vessels, intestines and other internal organs;
- the number of fingers on the upper and lower extremities;
- thickness and degree of maturity of the placenta;
- condition of the uterus and its appendages;
- amount of amniotic water.
The ultrasound study on the 2nd trimester allows you to determine the sex of the child with an accuracy of 90%, to identify the smallest violations in his development. After the screening, all the results and transcripts are attached to the card of the pregnant woman, and given to the doctor who leads the pregnant woman.
Screening of the 2nd trimester includes blood sampling from a vein, which is considered mandatory if you suspect pathology. If the ultrasound results are satisfactory, there is no suspicion of an abnormality, a blood test may not be prescribed. In contrast to the first trimester, a blood test at the 2nd trimester, estimates slightly other parameters, including:
- the amount of human chorionic gonadotropin (hCG);
- free estriol;
- alpha-fetoprotein (AFP) indicators;
- the content of inhibin A.
Ultrasound and blood tests during the second screening with an accuracy of 85% determine the dynamics of genetic abnormalities that were detected in the first trimester.
After passing all the tests, the results will be ready within a week. Only a doctor can decipher their results. With good screening results, serum ACE levels should be about 15 to 95 U / ml. With poor results, the protein level will be increased, which may be a sign of such pathologies as esophageal atresia, liver necrosis, umbilical hernia, and others. With reduced protein, the risk of developing Down syndrome or fetal death increases.
Screening rates of the 2nd trimester are very important for a pregnant woman and the fetus, therefore, it is very important not only to properly prepare for the examinations, but also to turn to a qualified doctor for decoding. It is important to understand that the life of the future child depends on the correct decoding.
How to prepare for the second perinatal diagnosis
For the second trimester screening special training is not required, but still to obtain reliable results, a woman must follow certain rules.
- Blood must be taken on an empty stomach. Eating any food, as well as liquids, can distort the results of the analysis. A blood test is best in the morning.
- 1 day before donating blood, you should refuse sweet foods, as well as products that may cause an allergic reaction.
- Ultrasound does not require any preparation. Filling the bladder is not necessary. Diagnostics can be done at any time of the day.
Many doctors in the field of obstetrics and gynecology insist that a woman needs moral preparation, support of native people. It is important for a woman to tune in to positive results, to hope and believe in good results.
When do this study take place?
Screening on the 2nd trimester of pregnancy is recommended not earlier than the 16th, but not later than the 20th week of pregnancy. Many doctors recommend diagnostics at 17-18 week. During this period, it is possible to accurately assess the condition of the fetus, to identify the slightest changes and pathologies in the development of the fetus.
If there are any abnormalities of the fetus or suspicion of them, in the second trimester other additional diagnostic methods may be prescribed. Pregnant women may be consulted by a geneticist and other specialists.
How is the study conducted?
Ultrasound and blood tests should be performed at the same clinic on the same day. These diagnostic methods do not cause inconvenience to a woman, except for those who are afraid to donate blood from a vein.
Ultrasounds are carried out by the transabdominal method, that is, the doctor applies the gel to the woman’s abdomen, using a sensor that contacts the skin, the doctor receives a picture on a computer monitor, from which it reads and records information about the condition of the fetus. The procedure takes from 15 to 30 minutes.
After the results of the ultrasound, identifying any pathologies, the doctor sends the woman to a biochemical blood test. In the case when there are any pathologies, a woman in the laboratory gives blood from a vein. The volume of a fence makes from 3 to 5 ml.
The results of laboratory diagnostics need to wait several days, while decoding ultrasound, can be obtained immediately after the procedure. After the results of the study, the doctor compares them with indicators of the norm and deviations. Against the background of the results of the examination, the specialist has the opportunity to get a complete picture, identify or eliminate pathologies, and give useful recommendations. If necessary, the pregnant woman can be appointed and other research methods.
Interpretation of the results
Screening of the 2nd trimester consists of indicators, each of which has its own norm. In some cases, the results may deviate from the norm, since everything depends on the duration of the pregnancy, the course of the pregnancy itself, the characteristics of the female body.
Depending on the clinic, laboratory, results may vary slightly, so doctors recommend to be examined only in clinics with a good reputation, where there is the latest equipment for laboratory and instrumental diagnostics.
The transcript of the ultrasound is a doctor uzist, and then passes to the attending physician. Deal with the analyzes, the results of the ultrasound can only doctor.
With increased or decreased rates, there is a risk of pathology in the fetus and the woman.
- A low level of AFP is a sign of Down syndrome, fetal death or incorrect determination of the duration of pregnancy.
- Increased AFP – malformations of the central nervous system, Meckel’s syndrome, liver pathology (necrosis).
- High HCG Down Syndrome or Klinefelter.
- Low hCG – high risk of Edwards syndrome.
- Reduced estriol – intrauterine infection, Down’s, placental insufficiency, risk of premature birth.
- Elevated estriol — internal maternal liver disease, multiple pregnancy, or large fetus.
A blood test is not the final result for deciding a final diagnosis. If pathology is suspected, amniocentesis is prescribed, which consists of piercing the abdominal wall with subsequent collection of amniotic fluid. The results of this test give accurate results on the condition of the fetus with a probability of 99%.
Despite the expected information about the indicators that may be present in deciphering the analysis and indicate the pathology of pregnancy, the final decision is made by the doctor and only after repeated and additional analyzes.
Standards of performance
To decipher the results of the examination, the doctor compares them with the normal table. If there are deviations, the specialist makes a conclusion, appoints additional or repeated analyzes.
To decipher the screening of the 2nd trimester, the doctor may build on the normal table.