After intercourse, the sex of the fetus is not determined by the woman, but by the sperm chromosomes provided by the man. If the sperm provided by the sperm contains x chromosomes, it is a girl, and if the sperm provided by the man contains y chromosomes, it is a boy. For women who are preparing for pregnancy by natural ovulation, there is currently no way to prepare for a boy, so there is no way to choose the sex of the fetus. This is because in the process of pregnancy preparation, men and women mainly have sexual intercourse, and men ejaculate semen into the vagina of women, and after the sperm is energized in the vagina, it will travel to the uterine cavity and fallopian tubes and then unite with the egg. At present, only artificial fertility can choose the sex, but the law in China does not allow it, and natural methods cannot allow women to conceive boys directly. Therefore, when men and women are preparing for pregnancy, they only need to take folic acid normally, do not stay up late or work hard, and try to eat a light and nutritious diet. If you do want a boy, then you can only consider IVF to choose the sex of the embryo and then choose a blastocyst containing the y chromosome to be transferred into the uterine cavity, but this situation must be allowed by law.