Current status of syphilis in pregnant women in Japan.

We examined the current status of syphilis-infected pregnant Japanese women, according to the results of syphilis screening and confirmation tests of women who gave birth in Japan between October, 2015 and March, 2016. We requested 2458 obstetrical facilities to provide information of syphilis screening tests and 78.1% of them responded. Considering the response rate and the rate of implementation of confirmation tests, the number of syphilis-infected pregnant Japanese women was estimated to be 250 (1/4022) per year.