The value of the gestational sac to identify the fetus is inaccurate and has no scientific basis.
After pregnancy can be based on the value of the gestational sac to deduce the approximate last menstrual period and pregnancy due date, as well as to understand whether it is in line with the normal gestational weeks, but can not be based on the value of the gestational sac to determine the sex of the fetus, there is no scientific basis.
At the beginning of pregnancy, the reproductive organs of the fetus have not yet developed, and it is impossible to determine the sex of the fetus simply by relying on the value of the gestational sac. Generally, when the reproductive organs of the fetus are well developed at about 16 weeks of pregnancy, the sex of the fetus can be determined by ultrasound, but now hospitals are prohibited from doing non-medical fetal sex identification.
It is recommended to have regular checkups after pregnancy. As long as the baby develops normally, it is the same for a boy or a girl.