China is a large country with hepatitis B. About 8% of the population is infected with HBV. The transmission routes of hepatitis B are mother-to-child transmission, blood transmission, close contact transmission and sexual transmission. Mother-to-child transmission is the most important transmission route for hepatitis B in China, and it is estimated that 40% to 50% of infected people are infected by mother-to-child transmission. If you do not receive the hepatitis B vaccine, 60% of children born to hepatitis B mothers can be infected with the hepatitis B virus within two years. 95% of children born to HBeAg-positive mothers will be surface antigen positive within one year. The time of individual infection with hepatitis B virus correlates with the percentage of chronicity of hepatitis B. The earlier the infection, the higher the percentage of chronicity of hepatitis B: 100% of those infected in the fetal period experience chronicity, 90% of those infected in infancy, 75%-80% of those infected in young children less than 2 years of age, 35%-45% of those infected in children 3-5 years of age, and in adolescents 6-14 years of age The chronicity rate of infection is about 25% in adolescents aged 6-14 years, and only 2%-6% in adults. The proportion of chronic hepatitis B patients who develop cirrhosis or liver cancer in the future is also related to the age of infection, which is about 25% in young children and 15% in older children and adults. Therefore, reducing and controlling the mother-to-child transmission of HBV is one of the most important measures to prevent HBV infection and to prevent cirrhosis and liver cancer. The incidence of intrauterine HBV infection ranges from 2% to 15% and occurs mainly in the third trimester (after 28 weeks). HBV infection is reported to occur in 85% of newborns as a result of blood and vaginal secretion exposure during delivery. The incidence of postnatal infection is lower and is similar to horizontal transmission due to close contact between mother and child. Hepatitis B vaccination is the best way to prevent hepatitis B. If newborns are vaccinated against hepatitis B within 12 hours of birth, the rate of mother-to-child transmission of hepatitis B will be reduced by 90%. in 1992, China’s Ministry of Health included the hepatitis B vaccine in the administration of planned immunization, but it was not free. in 2002, China’s hepatitis B vaccine was formally included in planned immunization, and the vaccine was free, and only the vaccination fee was required. all of it has been free since June 1, 2005. in more than 20 years, China’s neonatal hepatitis B vaccination In 1999, the national full vaccination rate for hepatitis B was 70.7%, and the first vaccination rate was only 29%; by 2010, the full vaccination rate for hepatitis B had increased to over 94%, and the first vaccination rate had increased to over 88%. From 2005 to 2012, the incidence rate of hepatitis B among children under 5 years of age decreased from 2.3/100,000 to 0.43/100,000, and that of children under 10 years of age decreased from 3.35/100,000 to 0.8/100,000, according to the survey. The implementation of neonatal hepatitis B vaccination has effectively protected children from hepatitis B virus, and the effect of hepatitis B prevention and control is remarkable. 2006 sero-epidemiological survey of hepatitis B shows that the rate of hepatitis B infection in the whole population in China has dropped to 7.18%, and the rate of hepatitis B virus infection in children under 5 years old is less than 1%. In 2013, the Obstetrics and Gynecology Group of the Chinese Society of Obstetrics and Gynecology issued the Clinical Guidelines for Prevention of Mother-to-child Transmission of Hepatitis B Virus, for HBsAg-negative pregnant women: newborns are vaccinated with hepatitis B vaccine according to a three-dose regimen at 0, 1 and 6 months of age, i.e., one dose within 24 h of birth, one dose at 1 month and one dose at 6 months, respectively, without HBIG injection. For HBsAg-positive pregnant women: within 12 h of birth, the newborn should receive one intramuscular injection of HBIG; at the same time, hepatitis B vaccine should be administered according to the three-dose protocol at 0, 1 and 6 months. For preterm infants: when the birth mass is ≥ 2000 g, follow the normal neonatal vaccination program. When the body mass <2000 g< span="">, the first dose of vaccine will be administered after the body mass reaches 2000 g, and then after an interval of 1-2 months according to the 3-dose protocol for 0, 1, and 6 months. If the pregnant woman is HBsAg negative and the premature baby is in good health, treat as above; if the health condition is not good, treat the related disease first and wait for recovery before vaccination. For HBsAg-positive pregnant women, regardless of the health condition of the preterm infant, one injection of HBIG will be given intramuscularly within 12 hours, and another injection will be required after an interval of 3-4 weeks; vaccination will be given within 24 hours, 3-4 weeks, 2-3 months and 6-7 months of birth, and follow-up will be conducted. Regarding breastfeeding of HBsAg-positive pregnant women, the guidelines recommend that after formal prophylaxis of the newborn, breastfeeding is feasible regardless of whether the pregnant woman is HBeAg-negative or positive. Regarding the mode of delivery and mother-to-child transmission, cesarean delivery cannot reduce the rate of mother-to-child transmission of HBV, and the guidelines do not recommend cesarean delivery for HBsAg-positive pregnant women to interrupt mother-to-child transmission. When other family members are HBsAg positive, HBIG must be injected if the newborn is in close contact with an HBsAg-positive member; without close contact, no injection is necessary. However, for mothers infected with hepatitis B virus, hepatitis B vaccination alone does not completely block mother-to-child transmission of hepatitis B virus. If hepatitis B immune globulin (HBIG) is not used, the failure rate of blockade with hepatitis B vaccine alone varies from 15-45%. With the combination of high potency hepatitis B immune globulin (HBIG), there are still about 10% of infants who fail blockade. Most of these immunization failures are caused by prenatal intrauterine infections, which are strongly associated with maternal serum HBV DNA levels. The higher the serum HBV DNA level of the mother, the greater the chance of mother-to-child transmission. Lowering HBV DNA in mothers with hepatitis B can reduce the rate of mother-to-child transmission of hepatitis B. However, the guidelines recommend anti-HBV treatment for HBsAg-positive pregnant women to reduce the rate of mother-to-child transmission: in the case of HBeAg-negative, no antiviral therapy is needed; in the case of HBeAg-positive, the guidelines do not give an opinion on this. The incidence of mother-to-child transmission of hepatitis B is related to serum HBV DNA load. Although there is also a relationship between HBeAg positivity and serum HBV DNA load, the classification by HBeAg negativity or positivity in this guideline is not very appropriate and is more direct than the classification by HBV DNA load. Antiviral drugs can effectively inhibit HBV replication and reduce maternal serum HBV DNA, but they need to be used with extra caution in pregnant women. The U.S. FDA classifies drugs into five categories according to their safety during pregnancy: Category A: animal experiments and clinical observations have not found any harm to the fetus; Category B: animal experiments have confirmed no harm to the embryo, but clinical studies have failed to confirm or no clinical verification data; Category C: only animal experiments have confirmed teratogenic or embryocidal effects on the embryo, but human studies lack data to confirm; Category D: clinical data have confirmed harm to the fetus. Class D: clinical data confirming the risk to the fetus, but the efficacy of the treatment of the disease in pregnant women is certain, and there is no substitute drug, and it is used after weighing the pros and cons; Class X: confirmed to be harmful to the fetus and prohibited during pregnancy. In the treatment of AIDS, lamivudine is classified as a class B drug with a safe level of use during pregnancy for mother-to-child blockade of AIDS. lamivudine, telbivudine, emtricitabine and tenofovir were classified as class B drugs for hepatitis B during pregnancy at a symposium of hepatologists in the United States in 2007. These drugs may be used if the benefits of their application for the mother and fetus outweigh the risks. Entecavir and adefovir have been classified in category C for their proven embryonic and fetal toxicity in animal studies. Plain interferon and pegylated interferon are contraindicated during pregnancy due to their antiproliferative effects. For pregnant women with immune tolerance, if HBV DNA > 106copies/ml (HBV DNA > 105 copies/ml by domestic reagents), lamivudine, telbivudine or tenofovir can be used after 28 weeks of gestation to reduce HBV DNA levels, and the infant can be blocked from mother to child after birth by combining hepatitis B vaccine and hepatitis B immunoglobulin, with a blockage rate of 100%. The rate of blockade can be up to 100%. Some people believe that nucleoside analogs can be discontinued after the birth of the infant, while others believe that antiviral drugs can be discontinued after 1-3 months. For women with chronic hepatitis B who are immunocompetent, they should be asked if they are planning to conceive or have children in the near future before initiating antiviral therapy, and if they are not planning to have children, they can use interferon or nucleoside antiviral therapy as appropriate. If she is planning to have children in the near future, interferon therapy is contraindicated, and with full informed consent, she should choose whether to use antiviral therapy according to the level of HBV DNA. Treatment. Although lamivudine can be used for mother-to-child blockade during pregnancy and has the most clinical safety data, its use as first-line antiviral therapy is no longer recommended in foreign guidelines because its resistance rate is too high for long-term treatment, and the long-term pros and cons should be weighed for the use in pregnant women with chronic hepatitis B who require treatment. Such patients should not discontinue antiviral therapy after delivery and should continue with the standard treatment for chronic hepatitis B. However, another question is whether the father can give birth if he is hepatitis B and is preparing or receiving antiviral therapy. This is not mentioned in the guidelines. The FDA pregnancy classification for drugs is for female pregnancy and does not include the effect of a man taking the drug on his wife’s fertility and fetal development. Currently, no national pharmacovigilance authority has a specific classification for the use of medications for male fertility. The process of fertilization is akin to a thousand horses squeezing a one-way bridge, with only one sperm winning the race to impregnate the egg. In general, drugs generally only affect the quality and quantity of sperm production, even if the drug affects the sperm, the problematic sperm is difficult to fertilize the egg, so the result of the drug may be to make his wife less likely to get pregnant, after which, whether or not the man takes the drug will no longer affect the development of the fetus in the mother’s body. Therefore, there is no global classification of the safety of fertility in wives while men are taking the drug. Because interferon has an anti-proliferative effect and is reproductively toxic, its instructions recommend contraception during treatment and for 6 months after treatment ends. But what about male patients receiving nucleoside analogs? The instructions for lamivudine, telbivudine, adefovir, and entecavir pairs have all stated information about reproductive toxicity and genotoxicity in male animals, and the results of preclinical animal testing of these drugs have shown no effect on the reproductive capacity of males. Only the instructions for entecavir state that “degenerative changes of the vas deferens were observed in rodents and dogs at doses of 35 times or more the human dose. No testicular changes were found in monkeys”. However, the doses used in animal tests are often dozens of times the doses used in human treatments. Theoretically, the administration of nucleoside analogues in men does not affect conception. Therefore, if a male patient has been treated with currently marketed anti-hepatitis B virus nuclear (acid) analogs, especially if he is taking lamivudine, telbivudine, or tenofovir, which are pregnancy category B, none of them will affect his wife’s pregnancy. A woman should not be advised to terminate her pregnancy because a man has impregnated his wife while taking a nucleoside analog.