Morphological or structural ultrasound: what it is, when to do it and what can be seen
Morphological obstetric ultrasound is a fundamental investigation in pregnancy, which serves to evaluate the development of the fetus and to identify any pathologies or malformations. In this article, we’ll tell you everything you need to know about this important exam.
Morphological ultrasound , also known as structural ultrasound , is the second of the obstetric ultrasounds offered free of charge by our National Health System.
Together with the dating ultrasound (performed in the first trimester) it is the most important examination of the whole pregnancy, because it allows for an in-depth evaluation of the development of the fetus and the structure of its organs, i.e. its ” morphology” .
Morphological ultrasound: when to do it and why?
Generally, this investigation is carried out between the 20th and 22nd week of pregnancy and for this reason it is also known as a second trimester ultrasound .
The reasons are essentially three. First of all, in this phase of gestation all the baby’s organs are already quite large and mature, and allow the presence of any pathologies or structural anomalies to be identified .
Additionally, there is an ideal amount of amniotic fluid within the uterus for observation.
Finally, beyond this period of gestation, the Italian law no longer provides for the possibility of abortion , since the child is in an advanced stage of development.
Premorphological ultrasound
In some particular situations, the gynecologist may decide to perform a morphological between 16 and 18 weeks : in this case, we speak of premorphological ultrasound .
Usually, this investigation is requested when there is a high risk of malformations , in order to be able to make an early diagnosis and carry out the necessary investigations in time (such as genetic tests for example).
After this exam, however, a “classic” morphology will still be performed at around 20 weeks.
Premorphological ultrasound: what can you see?
In this paragraph and the next, we will explain in detail what is seen during the morphological examination and which fetal measurements are taken. If you wish, however, you can view videos of two real morphological ultrasounds before reading further .
Although apparently it is a matter of a common ultrasound, the morphological is much more: in this period, in fact, it is possible to see clearly enough all the organs and bones of the fetus , which will be evaluated and measured to verify that the development is proceeding correctly.
Furthermore, it is precisely during the morphological obstetric ultrasound that the sex of the child is usually determined : for this reason, if you don’t want to know it, remember to notify the gynecologist before starting the examination.
Another very exciting detail is that the exam allows you to clearly see the profile of the future baby , as in the image of this little girl. They should also deliver one to you: it will be the first “photo” of your baby! Try to book the exam so that the future dad can also be present: the morphology is something special that will excite him too.
Measurements made
During the examination, the operator will analyze in particular:
- the brain and the cerebellum
- the heart , its chambers (atria and ventricles) and the frequency of the beat
- the digestive system (stomach, intestines, liver)
- the diaphragm and lungs
- the genitals and urinary tract
- the bones of the little hands and feet
- the spine
- the nasal cavities
- the eye sockets and the presence of the crystalline lens
- the lips
Furthermore, it will measure specific parameters to evaluate whether fetal growth is proceeding correctly and, specifically:
- the abdominal circumference
- the cephalic circumference (i.e. the circumference of the skull)
- the biparietal diameter (the distance between the parietal bones of the skull)
- the length of the femur and humerus
Finally, the gynecologist will also examine the umbilical cord (called the cord), the structure and position of the placenta (to see if it is inserted correctly), and the amount of amniotic fluid .
The result of the ultrasound depends on the skills of the operator who carries out the examination and on the quality of the machinery used, as well as on the position of the child and the conditions of the mother. If you are obese, for example, it may be difficult to have good visibility.
What is morphological ultrasound used for?
The morphological examination makes it possible to evaluate the growth of the child , to highlight the presence of any pathologies or malformations , and therefore to plan the appropriate interventions .
In some cases, for example, it may be necessary to deliver the baby in tertiary level centers (equipped with Neonatal Intensive Care Units), in order to be able to guarantee all the necessary care from the very first moments of life.
Morphological ultrasound: how does it work and how long does it last?
Ultrasound is a safe exam: it is performed with the use of ultrasound and does not involve any risk or side effect for mother and child . In particular, the morphology takes place in a “classic” way, ie with a probe placed on the abdomen and does not cause any discomfort.
The duration of the exam is highly variable . If the child is not in a favorable position, the appointment could last more than an hour. Alternatively, to make it turn, the operator could decide to temporarily interrupt the session to administer a sugary drink : this trick, more often than not, helps to make the child change position.
Furthermore, if there is a suspicion of particular anatomical malformations, the gynecologist could prescribe a second level ultrasound (i.e. performed in second level centers and/or by selected operators). In certain cases, a 3D or 4D morphological ultrasound may also be required .
Morphological ultrasound: how much does it cost?
This obstetric ultrasound can be performed free of charge through the National Health System . The important thing is to book it in time , as the waiting lists are extremely long.
The referral must include the exemption code relating to the current pregnancy week (e.g. M20 for the 20th week ). If this code is absent or does not correspond to the week of gestation in which the exam is performed, the cost of the ticket is around 50 euros .
Alternatively, morphological ultrasound can also be performed in private facilities , where the cost varies from 90 to 200 euros .
Morphological ultrasound videos
To get a preview of what you see during this exam, we present you two videos: the first shows the morphological ultrasound of a male , the second that of a female .
Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.
Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.