Sporty, the second ultrasound

Why sports? Because in the second trimester your future baby starts his acrobatics. This does not facilitate the practitioner's work. Yet at this point, there is a lot to see in the fetus ... including, if you like, his sex.

  • This ultrasound, called "fetal morphology", occupies a special place in the arsenal of screening: at 4 months, the future baby is fully formed, even if its organs are unable to function autonomously. "In the second trimester, the fetus floats in a sort of bubble filled with transparent amniotic fluid.The maturation of his nervous and muscular system will allow him to experience his first acrobatics," notes Dr. Ghada Hatem. Hence the interest of this review, sometimes difficult because of the sporting achievements of the future baby!

2nd echo, the details

  • It occurs between the 22nd and the 24th week of amenorrhea (counting from the first day of the last period), that is the 20th the 22nd week of your pregnancy.
  • It's the longest, Approximatly one hour. Why ? Because your baby moves a lot and is totally trained. There are many details to observe for the practitioner.

What is the purpose of this ultrasound?

  • The practitioner controls the size of the fetus, its movements and heartbeat. It checks that the growth of your future baby continues normally.
  • He takes precise measurements : biparietal diameter (of the head), abdomen and femur length.
  • He checks that the amount of amniotic fluid is sufficient, measures the thickness of the placenta and control the smooth running of the exchanges between you and your future baby.
  • He studies the functioning of organs in order to to detect major malformations or morphological abnormalities (observation of the placenta, umbilical cord, cerebral structures, face, spine, heart, etc.) that can lead to a chromosomal abnormality, such as trisomy 21.
  • Highly anticipated by parents, this ultrasound can also reveal the sex of the baby with a small margin of error. In rare cases, his position will prevent the practitioner from seeing his genitals. It will only be necessary to prolong the game of first names until the ultrasound of the third trimester.

The exams that can be associated with the second echo

  • In case of suspicion of chromosomal abnormality, a amniocentesis will raise the doubt.
  • A fetal blood puncture can also detect abnormal chromosomes, certain blood diseases, and if the fetus has been contaminated by an infectious disease developed by the mother (rubella or toxoplasmosis, for example). The collection, totally painless for you and your baby, is done under ultrasound control at the level of the umbilical cord.

Marie Auffret-Pericone with Dr. Ghada Hatem, gynecologist-obstetrician at the Bégin hospital of Saint-Mandé.

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