Clinical Study of STI Screening to Prevent Adverse Birth and New-born Outcomes

Description

Prevalence of STIs is high among pregnant women in South Africa and most infections remain untreated. Untreated infections impact on pregnancy and birth outcomes. Good diagnostic and point-of-care (POC) tests are available, such as the GeneXpert platform. The health impact, cost-effectiveness and approaches to optimization of STI diagnostic screening during pregnancy are unknown.

In order to 1) identify optimal, cost-effective screening strategies that decrease the burden of STIs during pregnancy and reduce adverse birth outcomes, 2) informs evidence to WHO's guidelines to introduce aetiologic STI screening globally and 3) elucidate the role of the vaginal microbiome in STI treatment outcomes, the investigators propose three Specific Aims:

1. Evaluate different screening strategies to decrease the burden of Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis among pregnant women and reduce adverse birth outcomes
2. Evaluate cost per pregnant woman screened and treated, cost of adverse birth outcomes, and cost-effectiveness per STI and disability-adjusted life-year (DALY) averted
3. Investigate the relationship between the vaginal microbiome and persistent Chlamydial infections in pregnant women

STI screening and treatment for Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis will be offered to HIV-infected and non-infected women (age >18 years) whom present for first antenatal care services. An effectiveness-implementation hybrid type 1 three-arm (1:1:1) randomized controlled trial (RCT), will be employed to evaluate different screening strategies to decrease the burden of Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis among pregnant women, and reduce adverse birth outcomes.

The costs of the different STI screening strategies relative to control will be estimated based on literature review and performance/implementation characteristics and compared, in addition to the costs of managing adverse birth outcomes. Decision analytic modelling will estimate the cost-effectiveness per STI, and DALY averted (Aim 2).

Study Aim 3 will recruit STI positive pregnant women to investigate the relationship between the vaginal microbiome and persistent chlamydial infection in pregnant women. Specifically, the investigators aim to:

1. Determine the impact of the vaginal microbiota on chlamydial treatment outcomes.
2. Explore the natural history of the vaginal microbiome in the context of antibiotic treatment for CT infections.

This is a case-control (1:2) study of chlamydia-infected pregnant women in South Africa using vaginal specimens collected at the first antenatal care (ANC) visit and daily thereafter for 3 weeks or longer if the follow-up test-of-cure result is positive.

Depending on the randomization arm, participants will be scheduled to be seen various times throughout pregnancy by the study team; antenatal care visits will be conducted in line with national policy. All post-partum mothers and infants will be asked to be seen at the first post-delivery clinic visit.

Details