Ultrasound is part of the gold standard for pregnancy testing and is harmless to the mother and the fetus. It helps early recognition of possible abnormalities of fetal development, genetic abnormalities (eg, Down's disease) and allows for the interruption of such pregnancy in a period of up to 12 weeks. At later stages of uzi, screening during pregnancy is assessed for further fetal formation, compliance with its size, gestational age, and placenta condition.
The first screening ultrasound in pregnancy
The first screening ultrasound during pregnancy is carried out at a period of 9-13 weeks. It is a very important method of diagnosis, which makes it possible to exclude the presence of gross defects in the fetus. During this period of pregnancy, many organs and anatomical structures of the fetus are already visible. On the first ultrasound, you can see the following:
- number of fruits, the place of attachment of the placenta, assess the condition of amniotic membranes. In case of multiple pregnancies pay attention to the number of placentas (in twins there is one common placenta, in twins separate);
- determine the gestational age and the expected date of delivery;
- to assess the correctness of the placenta and the formation of the umbilical cord;
- to reveal the signs of chromosomal defects. With ultrasound of the fetus with Down's syndrome, you can see: irregular outlines of the nose bones, increased thickness of the collar space, a change in blood flow through the tricuspid valve).
- identification of a number of malformations of the fetus;
- other pathological conditions (threat of abortion, signs of placental abruption).
The first ultrasound examination of the fetus, despite its careful implementation, can not give a 100% guarantee of the absence of anomalies in the fetus due to too small dimensions.
Second ultrasound screening for pregnant women
The second screening ultrasound of the fetus is performed at the 19-23 week of pregnancy and allows more accurate evaluation of the correctness of the fetal organs formation. During the second screening ultrasound during pregnancy, you can:
- determining the exact period of pregnancy;
- determination of the position and the present part of the fetus;
- determine the sex of the fetus;
- assess the location and condition of the placenta;
- determine the amount of amniotic fluid;
- to determine the state of the cervix.
The ultrasound of the fetal brain allows to exclude the anomalies of its development, to see the lateral ventricles and their vascular plexuses, the intermediate brain and the posterior cranial fossa. The ultrasound of the fetal brain is carried out sequentially in the craniocaudal direction (from the top down).
Third ultrasound screening for pregnancy
The third ultrasound screening for pregnancy is carried out at 32-34 weeks. Together with ultrasound, dopplerography and carotocography are performed, which allow assessing the fetal status of the fetus and the condition of the placenta. With the help of ultrasound it is possible:
- to reveal the defects of the fetus;
- to determine the position and presentation of the fetus, possible entanglement of the umbilical cord;
- to calculate the estimated weight and growth of the fetus;
- to assess the conformity of the fetus to the gestation period;
- assess the functional state of the placenta and its structure (density, thickness, maturity);
- measure the amount of amniotic fluid;
- assess the condition of the cervix;
- in women who had a cesarean section in history, assess the thickness of the scar on the uterus.
After the third ultrasound in a pregnant woman is determined pre-tactics of delivery.
So, we considered one of the methods how to do screening during pregnancy. As you can see, ultrasound is an indispensable diagnostic technique for revealing pathology in all trimesters of pregnancy, it allows to assess the condition of the placenta and fetus, and to establish the exact duration of pregnancy.