The recommended age for having a third child is usually before the age of 35, and there is no optimal age. Generally speaking, after the age of 35, the level of sex hormones in the body, physical condition and other aspects of the body has declined, the ovarian function gradually declined, increasing the risk of fetal malformation, and after 35 years of age, the pregnancy of its suffering from gestational hypertension, gestational hyperglycemia increased the chances of pregnancy, so it will also be to a certain extent on the life of pregnant women in danger. Before the age of 35, women’s ovarian functions and sex hormone levels are more stable, and their physical condition is better, so the chances of pregnancy complications and effects on the fetus are smaller, so women before the age of 35 can give birth to three children if their health permits. When considering the birth of a third child, it is best to do so before the age of 35, and the decision should be made under the guidance of a professional doctor after undergoing various examinations in a specialized hospital.