Study Population
The study population included pregnant women in the Maduo study, which
was a cluster-controlled, cross-over trial conducted in four antenatal
care clinics in Gaborone, Botswana. The primary aim of the main study
was to evaluate the impact of asymptomatic screening on post-delivery
prevalence and the vertical transmission of C. trachomatis orN. gonorrhoeae infections. Madua study details have been
previously described.(11) In brief, starting in February 2021,
consenting pregnant women in both arms were enrolled if they met the
following eligibility criteria: aged 15 years or older, attending their
first antenatal care visit, 27 weeks gestation or less, not treated for
an STI in the past 30 days, and without signs or symptoms of an STI
(most commonly vaginal discharge) and therefore not in need of syndromic
management (i.e. standard-of-care).
Initially two clinics participated in the study, one intervention and
one standard-of-care clinic (February 2021 to mid-September 2021). As
previously described,(11) clinics were similar in terms of patient
volume and services offered; however, one clinic had space readily
available for the screening intervention and was designated the initial
intervention clinic. However, COVID-related recruitment challenges
resulted in expansion to an additional two clinics, assigned to the
intervention arm, in mid-September 2021. In January 2022, the
standard-of-care clinic crossed-over and received the intervention and
two intervention clinics crossed-over and received the standard of care.
Our primary analysis sample included participants with non-missing
values for each of our key outcomes (low birth weight, preterm birth),
and non-missing values for covariates. We excluded participants who
experienced a miscarriage or stillbirth. We also restricted the sample
to participants with singleton pregnancies as non-singleton births are
more likely to have lower birthweight and shorter gestation.