The probability of having a son or daughter before and after ovulation is the same. Women ovulation body hormone level, the thickness of the lining is more suitable for fertilization of the egg bed, this time to arrange intercourse greatly improve the rate of conception, but does not affect the sex of the fetus. The sex of the fetus is mainly determined by the chromosomes of the fertilized egg. The chromosomes of the egg are only X. If the chromosomes of the spermatozoon are X, then it is a female baby, and if it is Y, then it is a male baby. The sex of the fetus is mainly determined by the chromosomes of the male sperm, which cannot be determined artificially and has nothing to do with whether the intercourse is before or after ovulation. Whether it is a boy or a girl, healthy growth and development is the most important thing, we suggest that pregnant women maintain a relaxed and happy mood during pregnancy, strengthen nutrition, timely checkups, and consult a doctor if they feel unwell.