During a fetal ultrasound, an ultrasound technician applies a special gel to the woman's abdomen or, in the case of a vaginal ultrasound, directly onto a special probe called a transducer which is inserted into the vagina. High-frequency sound waves are transmitted from the transducer and then bounce back to a computer that uses those sound waves to create an image of the fetus on the screen.
The following body structures in the developing fetus are usually examined during a routine fetal ultrasound:
- head and brain
- abdomen and stomach
- umbilical cord