Background: Syphilis requires a simple treatment but long-term follow-up because of the frequent re-infection. However, data regarding this issue remains limited.

Objective: To demonstrate the prevalence of incomplete follow-up visits in Thai heterosexual women who were diagnosed with syphilis and its associating factors.

Materials and Methods: The cross-sectional study was conducted by reviewing all medical charts of patients with syphilis at the Siriraj Female STI Clinic between 2012 and 2017. Eligibility criteria included Thai, heterosexual women 60 years or younger, no human immunodeficiency virus (HIV) infection, and no cancer. Venereal disease research laboratory (VDRL), as the serological follow-up test, was routinely done at 3, 6, 9, 12, 18, and 24 months after the treatment unless re-infection occurred. Incomplete follow-up was defined as that the patient came to the clinic for less than six months after completing treatment.

Results: There were 215 eligible patients with an average age of 25-year-old. One hundred twenty-eight (59.5%) had incomplete follow-up visits and 30 (14.0%) had not a single follow-up. The number of follow-up visits was 0 to 8 times (median=1) and the follow-up time period was 0 to 41 months (median=3). The diagnosis included primary syphilis (7/215, 3.3%), secondary syphilis (16/215, 7.4%), early latent syphilis (8/215, 3.7%), and late latent syphilis (184/215, 85.6%). Of them, 131 (60.9%) were pregnant. The associating factors with incomplete follow-up visits were age of 19 years or younger, lower education than primary school, and living in a nuclear family (OR 0.49, 95% CI 0.28 to 0.88; 1.29, 95% CI 1.04 to 1.61; and 1.41, 95% CI 1.06 to 1.89).

Conclusion: Over half of Thai heterosexual women with syphilis had incomplete follow-up visits. The associating factors include age of 19 years or younger, lower education than primary school, and living in a nuclear family.

Keywords: Associating factors, Post-treatment follow-up visits, Syphilis

Received 10 Jan 2020 | Revised 16 Jan 2020 | Accepted 17 Jan 2020