Globally, new HIV infections are concentrated in eastern and southern Africa where the infections are largely acquired by women outside of known key populations. Identifying African women at high risk for HIV acquisition and successfully engaging them in HIV prevention services, particularly pre-exposure prophylaxis (PrEP) programs, is an urgent global health priority. The U.S. President's Emergency Plan for AIDS Relief program in Africa typically relies on self-reported risk screening tools (SRST) to target HIV testing and refer individuals for PrEP. However, these tools have low to moderate sensitivity, missing many women at high risk for HIV. This is partly due to underreporting of risk factors, but also because many African women are at heightened HIV risk solely through relationships with high-risk male partners. Moreover, many African women enrolled into PrEP programs stop using PrEP within months of initiation. Decades of research shows that curable sexually transmitted infections (cSTI) are objective markers of future HIV risk, but cSTI testing largely has been omitted from African HIV programs. With the advent of lower cost multiplex cSTI testing and point of care diagnostics, there is new opportunity to determine whether integrating female cSTI testing services into HIV programs can improve HIV epidemic control. Here, the investigators will conduct an individually randomized effectiveness implementation trial of SRST plus cSTI diagnostic testing for chlamydia, gonorrhea, trichomonas, and syphilis compared to SRST alone to increase PrEP use among cis-gender African women aged 15-39 years. The investigators hypothesize that cSTI testing will increase PrEP use primarily through (i) improved identification of women at high risk for HIV and (ii) enhancement of self-perceived HIV risk. The proposed research will be nested within the Rakai Community Cohort Study, a population-based HIV surveillance cohort in Uganda. In Aim 1, \ 4,500 HIV-negative women will be individually randomized 1:1 to PrEP screening based on SRST plus cSTI diagnostic testing (intervention) versus PrEP screening based on SRST alone (control arm). Both arms will be offered syndromic case management for cSTIs and syphilis testing for pregnant women (standard of care). The primary outcomes will be PrEP uptake, adherence, and persistence, assessed through clinical records and drug level testing. In Aim 2, the investigators will perform a mixed-methods, implementation science evaluation of female cSTI testing for HIV prevention and control. The investigators will use qualitative and quantitative methods to assess the mechanisms, barriers, and facilitators to improving PrEP outcomes through cSTI testing and how this varies by cSTI pathogen, SRST outcomes, and demographic profiles. In Aim 3, the investigators will use mathematical models to evaluate different cSTI testing approaches to reduce HIV incidence at a population level by considering what cSTIs to screen for, in what health care settings, and at what cost thresholds. The investigators will also model broader health benefits of cSTI testing. Results from this study will provide actionable, population-level information to inform strategic delivery of high impact HIV prevention through integrated HIV and cSTI programming in Africa.