Ultrasounds are some of the most exciting moments of pregnancy, both for its diagnostic value, and for the possibility of seeing your baby move and grow inside you.
An ultrasound is a non-invasive technique, based on ultrasound, that allows you to see organs and structures within the body. In the case of pregnant women, they are used to examine the baby inside the womb, providing very valuable information about the well-being, position, age or weight of your baby. It also allows to determine the situation of the placenta and the quality and quantity of the amniotic fluid, as well as possible complications or abnormalities that may affect your pregnancy.
In a normal pregnancy, three ultrasounds are usually performed:
The first around 12 weeks. In it, pregnancy is confirmed, the number of babies and gestational age are determined and Triple screening is carried out (a screening test that measures the risk that your baby suffers from certain abnormalities).
The second (morphological ultrasound) is performed around 20 weeks. In it, the morphological characteristics of the baby are analyzed to know if it is developing normally.
The third is done around 34 weeks to check the status of your baby, the amniotic fluid and the placenta.
Morphological ultrasound: what it is and what it is for.
Morphological ultrasound allows assess whether your baby is developing within the appropriate parameters. In it, the anatomy and biometrics of your baby's organs are analyzed.
Is done between 20 and 22 weeks since this is an optimal gestational age to be able to assess the morphology of the baby: At younger ages, the organs may not have finished forming or may still be too small to be seen clearly and, at later ages, the quality of image may be diminished. In addition, at this point in the pregnancy, if a malformation is diagnosed, the parents still have time to decide whether or not to continue with the pregnancy. Beyond 22 weeks, the law only contemplates the interruption of pregnancy in very specific cases.
What information does morphological ultrasound provide us?
The morphological ultrasound is the test that evaluates that your baby has all his organs and bones well developed with respect to his gestational age. A complete anatomical study is performed in which it is verified that the organs function normally, that their limbs are well formed, the spine well aligned, that the profile of the face is normal and that they have all the fingers and toes. Also biometrics is studied taking measurements of the diameter of the head, length of the femur and humerus, nuchal fold, etc., which are compared with percentile tables, and allow you to check that your baby's growth is adequate.
In addition to the anatomical characteristics, other important things are measured such as the location of the placenta, the insertion of the umbilical cord into it, the amount of amniotic fluid, the length of the cervix or the blood circulation through the uterine arteries. All these parameters will provide information on how the pregnancy can go.
What is the accuracy of the test?
It is estimated that this ultrasound can detect 88,3% of major malformations of the nervous system, 84% of kidney malformations, and 38% of those related to the heart and large blood vessels. However, also there are some limitations that can hinder the diagnostic ability of ultrasound: An obese mother, intestinal gases, uterine fibroids, the position of the baby, the resolution of the ultrasound scanner or the experience of the person performing the test, can be decisive in the quality of the information provided by the ultrasound.
But not everything will be measurements and diagnoses. This ultrasound can also be very exciting since, if you wish, you will be able to know the sex of your baby. It is also an ultrasound that lasts a long time and in which you can see your baby for a long time, so Relax and enjoy that unique moment!