Breakdown of the Anatomy Scan
Whether or not you want to know your baby’s gender before birth, an ultrasound will be recommended mid-way through pregnancy to ensure your baby’s body has developed as expected. This ultrasound is known as the ‘Anatomy Scan.’
The Anatomy Scan
Between 18-21 weeks, you can have a more in-depth ultrasound done to determine your baby’s size, weight, and to measure growth, ensuring everything is developing according to plan.
In addition, the anatomic ultrasound looks at and takes measurements of the different anatomic parts of the baby. The technician or doctor will be looking for any signs of slower than normal development.
The skeleton should be hardening at this point and the gender of the baby should be visible. In many cases, the baby may have their legs crossed or be facing away from the abdomen and thus the sex organs will not be visible. If your baby cooperates, you will learn the gender! You should also receive many pictures of your little one! (Make sure to record the heartbeat as well.)
The following fetal parts are checked during the anatomy ultrasound:
Depending on the positioning of your baby, the technician may or may not be able to detect if your baby has a cleft lip.
The technician will be assessing the fluid-filled spaces inside the brain and the shape of the cerebellum, which is in the back of the brain. They will also be able to identify if any cysts are in the choroid plexus, a tissue in the brain that produces cerebrospinal fluid. Fetal cysts may indicate an increased risk for a chromosome abnormality (or may disappear by the third trimester).
Looking at the shape and skull integrity
Checking for nuchal fold thickness
Your baby’s spine will be evaluated vertically and horizontally. The technician is checking that the vertebrae are in alignment and that the skin covers the spine at the back.
The rate, rhythm, 4-chamber views, and outflow tract are evaluated. Congenital heart defects can be seen, and a prenatal diagnosis will prepare you and your medical team to provide your infant with the best medical care possible!
The lungs and diaphragm are checked and evaluated.
There will be a good look at the stomach, kidneys, liver, bladder wall, umbilical cord, and abdominal circumference.
Specifically, the femur, tibia, fibula, humerus, radius, ulna, hands, and feet will be measured.
Baby’s gender will be noted, and any genital abnormalities can be identified.
The mother’s cervical length will be measured
Based upon the results of the measurements, the gestational age of the baby will be predicted based upon the average size of other babies scanned during their 20th week of pregnancy. If any abnormalities are found, additional examinations will be recommended.