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

This study aims to evaluate different screening strategies to decrease the burden of Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Trichomonas vaginalis (TV) among pregnant women, and reduce adverse birth outcomes. In turn it aims to evaluate the cost per pregnant woman screened and treated, cost of adverse birth outcomes, and cost-effectiveness per sexually transmitted infection (STI) and disability-adjusted life-year (DALY) averted. Furthermore, this study will incorporate a vaginal microbiome sub-study aimed to investigate the relationship between the vaginal microbiome and persistent Chlamydial infections in pregnant women.

Aim 1 and 2: The intervention includes diagnostic testing at a woman's first antenatal care visit using the Xpert® platform with same-day treatment for Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis infection with either a test-of-cure three weeks post-treatment (arm 1) or a repeat test at 30-34 weeks gestation (arm 2) compared to the standard of care, i.e. syndromic management (arm 3).

Aim 3: Case-control study to investigate role vaginal microbiome in STI treatment outcomes

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).

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.

Eligibility Criteria:
Inclusion Criteria for pregnant women:

1. Age≥18 years
2. Currently pregnant based on positive urine pregnancy test
3. Attending first ANC visit for current pregnancy
4. Gestational age \<20 weeks
5. Agreeing to nurse-collected specimens
6. Resident in Buffalo City Municipality (BCM)
7. Intent to deliver in one of the four midwife obstetric units (MOUs) in BCM

Gestational age will be confirmed via ultrasound

Exclusion Criteria:

1. Planning to relocate during pregnancy or deliver in an MOU outside of BCM
2. Unknown HIV status (e.g. refusal, invalid test result)
3. Currently participating in another ANC/HIV study
4. When the ultrasound confirms ≥20 weeks gestation at first ANC

Inclusion criteria for Neonates:

1) born to mothers that provided informed consent to participate in study, 2) provision of updated verbal consent by mother to collect and test specimens for STIs