Ultrasound during pregnancy has a diagnostic objective, it consists of visualizing the fetus inside the mother's womb to detect any abnormality and carry out an exhaustive follow-up of the fetus during pregnancy. Thanks to ultrasound, future parents can also see the image of their child before birth, and gynecologists can check that everything is fine in the fetus, the placenta, the amniotic fluid and other anatomical elements involved in pregnancy.
Ultrasounds they allow the gynecologist to "see" the baby before birth. There are several types of ultrasounds or ultrasounds, in 2D, 3D and 4D.
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How many ultrasounds should be done and in what weeks?
During the control of a pregnancy The number of ultrasounds to be performed may vary depending on different factors, for example if it is a low risk pregnancy or a high risk pregnancy obstetric. The gynecology specialist will plan how many ultrasound are necessary to perform.
With a normal pregnancy the usual number of ultrasound is:
- First trimester ultrasound. It takes place between 6th and 10th week. Is the first ultrasound of pregnancy. Its objective is to know the number of embryos and to establish more precisely the gestational age.
- Second trimester ultrasound. It takes place between the 11th and 13th week. Its objective is to assess the anatomy of the fetus and review the markers that allow calculating the risk of Síndrome de Down.
- Morphological ultrasound. It takes place between 20th and 22th week. This is the most thorough obstetric ultrasound of pregnancy. In it, a complete assessment of all the organs of the fetus is carried out, the objective of which is to rule out the presence of structural abnormalities. It is also analyzed uterus and placenta in order to have more information about the evolution of the pregnancy.
- Third trimester ultrasound. It takes place between 30th and 34th week. The objective of this ultrasound is to assess the fetal growth, the amount of amniotic fluid and see if there is any fetal pathology.
A last ultrasound is also performed on the 39th or 40th week of delivery to assess that the fetus is in a correct position and its size.
When they occur risk pregnancies, multiple pregnancies (twins, triplets, etc.) or other special cases, more ultrasounds are performed depending on the circumstances.
Types of ultrasound
Ultrasounds can be 2D, 3D y 4D. The 3D y 4D allow parents to see their future child better and may even have the video in the case of the 4D echo to see later.
Two-dimensional ultrasound, is the most common in our environment, is two-dimensional and is shown on a monitor while the gynecologist performs the examination. It may take several attempts to obtain a clear ultrasound image if the fetus is in motion. Moving images will be visible on the monitor, but they are flat and black and white.
These 2D ultrasounds are the usual in many clinics and hospitals when performing a fetal diagnosis. It is difficult for parents to distinguish anything in the photo taken from a 2D ultrasound.
It is an ultrasound in which 3-dimensional still images are seen from the two-dimensional ultrasound that is usually performed.
A Echo 4D It is a non-invasive technique and without risk for the baby or for the pregnant woman. A transducer is slid over the abdomen of the pregnant woman, allowing the images to be captured that reveal details of the fetus. Unlike the 3D ultrasound, a 4D ultrasound It consists of the sequence of moving 3D images in real time.