1, reduce the wife’s fertility Research data show that after the husband is 35 years old, the wife’s chance of pregnancy decreases by 3% per year. 45 years old or older men than those under 35 years old, the time required for his wife to get pregnant is 5 times longer. 2, increase the risk of miscarriage for the wife Pregnant women whose husbands are older than 35 years old have a 30% increase in the chance of spontaneous miscarriage between 2 and 4 months after pregnancy. 50-year-old men have double the risk of spontaneous miscarriage for their wives compared to 20-year-old men. 3, increase the risk of disease and even death of the baby Statistics show that the disease and death rate of the baby increases with the age of the parents, and so far about 20 different diseases have been found to be related to the aging of the father. For example, children born to fathers over the age of 40 have a deformity rate that is one times higher than that of “young fathers”, and babies born to men over the age of 50 are almost three times more likely to suffer from schizophrenia than those born to men under the age of 50. For every 5 years that a father’s age increases, the chance of his baby having insulin-dependent diabetes increases by 9%, etc. In summary, there are many problems with having children at an advanced age, and it is best to have children when you are in the best physical condition. The best age for men to have children is between 30 and 35 years old, when male sperm quality is at its peak. During the age of 25-29 years, women are fully developed and have high quality eggs, with low risk of delivery, good fetal growth and development, and the lowest incidence of premature births, malformations and dementia.