The follow-up of infants born to pregnant women with syphilis should be carried out according to the following protocol: 1. Infants born to pregnant women with syphilis who have undergone adequate treatment: ① At birth, if the infant is positive for serum RPR reaction, it should be re-examined once a month; at 8 months, if it is negative and there are no clinical signs of congenital syphilis, observation can be stopped. ②If the infant is born with negative serum reaction, it should be rechecked at 1 month, 2 months, 3 months and 6 months after birth, and if it is still negative at 6 months and there is no clinical manifestation of congenital syphilis, syphilis can be excluded. ③If the infant is born with a positive seropositive reaction, it should be followed up, and if it is still positive at 1.5 years, it should be treated immediately. ④If the titer gradually increases during the follow-up period or the clinical manifestation of congenital syphilis appears, it should be treated immediately. 2. Infants born to pregnant women with syphilis who have not been adequately treated or treated only 4 weeks before delivery or not treated with penicillin may be treated with prophylactic syphilis treatment for the infant and supplemental treatment for the pregnant woman.