How long does it take to do ultrasound to check the gender of the baby?

The baby's gender has been determined from the day of fertilization. Although it is strictly forbidden in our country for doctors to examine the fetus for gender identification, it must be admitted that B-ultrasound is the most accurate way to identify the gender of the fetus! So, how long does it take for an ultrasound to tell whether it is a boy or girl during pregnancy? Let’s learn about it below.

How long does it take to do ultrasound to tell if a man is a woman?

Medically speaking, B-ultrasound examination can be performed around 20 weeks of pregnancy to identify the sex of the fetus, provided, of course, that the fetus is in the right position and the ultrasound doctor can see the key parts of the baby. At this stage, the differences between boys and girls are already very obvious. As your pregnancy progresses, these differences will become more recognizable. If your baby is surrounded by enough amniotic fluid and his feet are not tucked between his legs, then the gender of the baby can usually be determined based on the B-ultrasound data in the late pregnancy.

It should be noted that the current predictions of fetal gender based on fetal movement, fetal heartbeat, and fetal sac width ratio that are widely circulated on the Internet are all inaccurate. B-ultrasound observation of the fetus's sex is to look at the male reproductive organs, not the gestational sac. Starting from around 11 weeks (80 days) of pregnancy, babies of different genders begin to show differences in appearance. At this time, the positions of all the fetus's sexual organs are prominent. In boys, this protrusion usually extends upward and intersects the spine at an angle of more than 30 degrees. Relatively speaking, the protruding position of a girl's genitals will appear to be more horizontal, and the angle between them and the spine is less than 30 degrees.

Other ways to check the sex of the fetus

A blood test is a quick way to determine the sex of the fetus. However, China currently does not have the technology to identify the sex of the fetus through blood tests. The closest region to having this technology is Hong Kong. Researchers have discovered that a gene called "SRY" only exists on the Y chromosome. Once its presence is detected, it means that the fetus is male. Therefore, the fetal DNA in the mother's blood is isolated to see if the SRY gene can be found, and the gender question is naturally solved. Unlike B-ultrasound, which can only detect gender characteristics when the fetus is large enough, this type of examination can be performed 7-8 weeks after pregnancy, and its accuracy is higher than B-ultrasound, reaching 99.4%.

However, it should be noted that the following criteria must be met when doing blood fetal gender identification: the gestational age is more than 8 weeks, no pregnant woman has given birth to a male fetus within one year, no intravenous injection, major surgery, liver transplantation has been performed within one year, and the blood type is a normal human blood type. Otherwise, the accuracy of blood tests will be greatly reduced.