Major pregnancy study
The second trimester is the time when the fetal organs are already formed and large enough for detailed examination, and there is still enough space in the uterus for good visualization. The doctor sequentially evaluates the brain, face, spine, heart with its chambers and great vessels, lungs, abdominal organs, kidneys and limbs. It is at this time that most developmental defects are detected. At the same time, the length of the cervix is measured - its shortening is the main predictor of premature birth and requires timely intervention. The location and structure of the placenta and the amount of amniotic fluid are also assessed.
Why are timing screenings needed?
It is no coincidence that ultrasound examinations during pregnancy are carried out at certain times: each window shows its own signs. At 11–14 weeks, the thickness of the nuchal translucency and nasal bone are assessed - markers of chromosomal abnormalities that later disappear. At 18–22 weeks, the formation of organs allows for a detailed examination of the anatomy of the fetus. In the third trimester, the main things are growth, fetal position, condition of the placenta and blood flow.
Missing the screening window means losing information that cannot be obtained at another time.
What is being assessed
- heart rate, number of fetuses and gestational age
- fetometry - dimensions and compliance with deadlines
- anatomy of organs and identification of malformations
- localization, structure and maturity of the placenta
- amount of amniotic fluid
- blood flow in the arteries of the umbilical cord, uterus and fetal vessels
Security
Ultrasound during pregnancy has been used for more than half a century and is recognized as safe when used for medical reasons. International recommendations advise not to conduct research without indications solely for the sake of photos or videos, and also to limit the duration of exposure - the principle of reasonable sufficiency.