Syphilis that occurs during pregnancy is called gestational syphilis and can either be formed by the patient’s pregnancy or can be the result of infection during the pregnancy. Syphilis in pregnancy not only affects the health of the pregnant woman, but also the development of the fetus, leading to miscarriage, premature birth, and stillbirth. Even if the pregnancy is maintained until delivery, the chance of the baby being born with congenital syphilis is high. Some fetuses, although developing normally, are still at risk of infection from contact with genital lesions during passage through the birth canal. It is well documented that the fetal survival rate of untreated women with early-onset syphilis is only about 50%, and most fetuses will become congenitally syphilitic. Although the fetal survival rate of women with early latent syphilis is around 80%, more than half of the children will become congenital syphilis children in early childhood. Women of childbearing age should cooperate with their doctors, seize several key moments and take the following preventive and control measures: 1. Pre-conception screening. Dominant syphilis can be diagnosed through history and signs; latent syphilis can only be confirmed through laboratory tests. The latent syphilis is the main reason for the occurrence of syphilis in pregnancy. Therefore, women of childbearing age should be tested for syphilis serology before planning a pregnancy. If you are found to be infected with syphilis, you should suspend pregnancy and undergo systematic treatment first. At the same time, the spouse should be examined and the timing of pregnancy should be decided under the guidance of the doctor. 2. Screening and anti-syphilis treatment should be carried out within 3 months of pregnancy. If a pregnant woman is diagnosed with syphilis infection, it is better to choose abortion; also, under the guidance of a doctor, adequate syphilis repellent treatment can be carried out. This is because before 16 weeks of pregnancy, the fetus is fed by the chorionic villi, which consists of two layers of cells that the syphilis spirochete cannot easily cross. After 16 weeks of gestation, the placenta is used to supply the fetus with nutrients because the trophoblast cells in the placenta are gradually shrinking, and the syphilis spirochetes can pass through the placenta and enter the fetus. Regardless of whether treatment has been carried out before pregnancy, in order to ensure that the syphilis spirochete in the pregnant woman is no longer pathogenic, the patient should undergo adequate treatment again after pregnancy. 3. When the test result is suspiciously positive, regular follow-up review and treatment should be carried out. If there is a positive reaction but the titer is low, false positive conditions (e.g. autoimmune disease, connective tissue disease, viral infection, non-syphilis spirochete infection) should be excluded. False-positive reactions to the syphilis spirochete serologic test have also been seen in late pregnancy. If the cause of the false-positive reaction cannot be found, the pregnant woman should be treated with anti-syphilis treatment. 4. When syphilis is detected in the middle and late stages of pregnancy, the pregnant woman should determine whether the fetus is infected along with timely treatment. ①B ultrasound examination. If the fetus is found to have characteristic scalp edema, the fetus should be suspected to be infected with syphilis. ②Fetal amniotic fluid should be collected immediately for dark-field examination, and the finding of syphilis spirochetes can be used as a basis for the diagnosis of fetal infection. ③At delivery, if the umbilical cord and placenta are examined for abnormalities, the fetal surface of the umbilical vein wall and placenta can be scraped for dark-field examination. ④Venous blood can be collected for laboratory tests after the birth of the baby, and the diagnosis can be confirmed if the titer of non-syphilis spirochete antibody (RPR) continues to rise or is higher than the mother’s level. 5. Determine the treatment plan. Procaine penicillin G 800,000 μ/day, intramuscularly. For those allergic to penicillin, erythromycin 500mg/day/4 times orally. Early stage patients need to be treated for 15 consecutive days, and patients with syphilis above stage II need to be treated for 30 consecutive days. To avoid adverse reactions that negatively affect the fetus, it is recommended to avoid the use of Bianxin penicillin. 6. If the patient has no syphilitic lesions on her breasts, she can breastfeed her healthy baby.