Ultrasounds have a variety of purposes during pregnancy, but the use that often receives the most attention is its ability to reveal the sex of the baby.
Some parents-to-be can’t wait to find out whether they’re having a boy or a girl, while others choose to put off knowing the sex until birth. Either way, a sonogram — the grainy, black-and-white image that results from an ultrasound scan — will be the baby’s earliest picture and a couple’s first chance to see the developing fetus.
Ultrasound uses high-frequency sound waves to produce an image on a screen of the baby in the mother’s uterus. The scans are typically done twice during pregnancy, but the one did between 18 weeks and 22 weeks is when the sonographer (ultrasound technician) might identify the gender of the baby if parents want to know.
Gender prediction test made by ultrasound has a 90% accuracy rate. But mistakes can be made when determining gender because it depends on the clarity of the images and the skills of the person interpreting them.
Until the 14th week of pregnancy, baby boys and girls look exactly the same on ultrasound. Beyond this point, noticeable anatomical differences in the genitals can show up on the scan. For this reason, we do sex predictions by ultrasound starting at 15 weeks.