It is generally considered more appropriate to give birth between the ages of 25 and 29. 1.25 to 29 years old: the female reproductive system is fully developed, generally high quality eggs, relatively small risk during delivery, for the later growth and development of the fetus is better, preterm delivery and the incidence of malformation is lower. 2. too late to give birth: with the age of 35 years old, especially after the ovarian function began to decline, the quality of eggs, pregnant women accompanied by a variety of diseases, such as high blood pressure in pregnancy increases the likelihood. 3. Too early: due to the young age, the body is not fully developed, may affect the health of the body, but also increase the risk of uterine disease. Moreover, assuming the responsibility of teaching and raising children too early may affect the organization of work, study and family life. Women are advised to choose a reasonable age for childbearing and, if they intend to have children, to maintain regular living habits, reduce exposure to environments with radiation, and exercise appropriately to strengthen their physical fitness.