Having a son depends on whose genome

The birth of a son mainly depends on the father's sex chromosomes. Human gender is determined by sex chromosomes. Men carry XY chromosomes and women carry XX chromosomes. When the sperm carrying the Y chromosome combines with the egg, the embryo develops into a male.

Male sperm is divided into two types: X-chromosome-containing and Y-chromosome-containing. The ratio of the two types is theoretically half. Y-chromosome sperm are smaller in size, swim faster but have a shorter survival time, and are more active in alkaline environments. Factors such as the pH of the female reproductive tract and the timing of intercourse during ovulation may affect the survival probability of Y-chromosome sperm, but the sex of the fetus is essentially determined by the type of chromosome carried by the sperm at fertilization.

Some special circumstances may affect the sex ratio. For example, patients with certain genetic diseases have defects in the Y chromosome, which may lead to reduced fertilization ability of Y sperm. In rare cases, sex chromosome mosaicism may occur during embryonic development, but these cases are very rare. Folk methods such as diet adjustment and sexual intercourse postures lack scientific basis and cannot change the rules of chromosome combination.

During pregnancy preparation, it is recommended that both couples maintain a regular schedule and avoid exposure to harmful substances. Men can appropriately supplement trace elements such as zinc and selenium to maintain sperm quality. If there is a family history of genetics or long-term pregnancy preparations have failed, pre-pregnancy genetic counseling may be considered. However, fetal gender screening is a prohibited item in my country that is not medically necessary and should follow the natural laws of fertility.