First of all, I want to know what pH values boys and girls can check, sour children, hot women ... these are not reliable. The only reliable way is to look at the sex of the fetus in the abdomen through advanced medical equipment. This is B-ultrasound, and only it can judge the sex of the fetus.
Now, boys and girls are the same, so don't worry about the sex of the child. Boys and girls are gifts from the sky, so we should cherish them.
To sum up, it is impossible to know the sex of the child by checking the pH value.