With the liberalization of the policy, preparing for the second child has become a part of the life of more and more couples of childbearing age, and some couples are already over 40 years old and want to take the second child to add a companion to the oldest. As most of the couples preparing for second pregnancy are older, the corresponding pre-conception preparation is insufficient, especially the lack of understanding of the physical condition, a number of pregnant women with second pregnancy have embryonic sterilization or developmental abnormalities, and suffer serious physical and mental injuries, so couples with second pregnancy should make adequate preparations before conception. (a) A routine checkup right before pregnancy. It should mainly include routine blood (including blood type), routine urine, routine stool, liver and kidney function, A function, five items of hepatitis B, chest X-ray, routine white belt, TORCH (full set of decompensation), female endocrine, male semen routine, etc. Some people think that the second child will not have problems because the first pregnancy and delivery went very well, but this is not the case. The main reason is that the time between the second child and the first child is longer, 5-10 years old is more common, a few as much as 15 years old or more, because with the growth of age, changes in fertility is inevitable, many mothers of second children have passed the age of high risk of childbirth (35 years old), so pre-conception medical examination is very necessary to detect problems in a timely manner. (B) timely and reasonable vaccine refills At present, there are two vaccines that experts recommend are best to be able to play. One is rubella vaccine; the other is hepatitis B vaccine. Because once the mother-to-be is infected with these two diseases, the virus will spread vertically to the fetus, causing serious consequences. 1, rubella vaccine: at least 3 months in advance of the injection, more than six months is best. 2.Hepatitis B vaccine: Injected one year in advance. Because the hepatitis B vaccine has a total of 3 shots, the second shot will be injected 1 month after the first shot, and the third shot will be injected at the age of 6 months. Generally 3-4 months after the end of the third injection, the hepatitis B vaccine virus in the body completely disappears, producing antibodies. Some people do not produce antibodies after 3 injections and sometimes need to be re-injected. (C) Improve lifestyle habits 1. Quit smoking: Studies have shown that smoking can cause sperm malformation, which reduces the production and vitality of sperm. The harmful ingredients in tobacco can cause the ovarian function to decline and cause infertility; smoking also affects the development of fertilized eggs and increases the chances of miscarriage, or cause ectopic pregnancy, fetal malformations. 2, a small amount of alcohol: a large amount of alcohol on the sperm, eggs have obvious damage, sometimes more than 2 months of damage. 3. Regular work and rest. 4, healthy diet: do not eat harmful food, less coffee, carbonated drinks, soft drinks, etc. 5, do not have pets. Avoid the damage of harmful parasites in the body of animals. (iv) Take additional folic acid in the first trimester of pregnancy. (v) Take prescription drugs carefully. If you are ill and need to take medication, be sure to choose medication that does not affect pregnancy or extend the time of pregnancy preparation. (vi) Take basal body temperature or use ovulation test paper to understand the ovulation pattern.