According to Duke Zhou, having a boy in spring is divination in spring, having a child in spring is a boy, and having a girl at other times. This is just a statement in metaphysics, and the reason is not clear. After all, some people believe it and some have been verified by facts, but many pregnant mothers think it is false, and there is no such thing at all.
It can be said that the gender of a woman's child after pregnancy is a probability event, which does not mean that pregnant women can have children of any gender if they want to. Let's take the most popular saying among the people. Hot and sour girl? Generally speaking, this statement has no scientific basis. It is a normal physiological phenomenon caused by female pregnancy, and has nothing to do with the sex of the fetus.
Since many online claims are not credible, how can we know the sex of the fetus? The answer is definitely yes. After all, medical technology is developing rapidly now, but the state forbids this technology to identify the sex of non-therapeutic fetuses.