Abstract:
Background: Preventing unintended pregnancies is paramount for women living with HIV (WLHIV). Previous
studies have suggested that efavirenz-containing antiretroviral therapy (ART) reduces contraceptive effectiveness of
implants, but there are uncertainties regarding the quality of the electronic medical record (EMR) data used in these
prior studies.
Methods: We conducted a retrospective, cohort study of EMR data from 2011 to 2015 among WLHIV of
reproductive age accessing HIV care in public facilities in western Kenya. We validated a large subsample of records
with manual chart review and telephone interviews. We estimated adjusted incidence rate ratios (aIRRs) with
Poisson regression accounting for the validation sampling using inverse probability weighting and generalized
raking.
Results: A total of 85,324 women contributed a total of 170,845 women-years (w-y) of observation time; a subset
of 5080 women had their charts reviewed, and 1285 underwent interviews. Among implant users, the aIRR of
pregnancy for efavirenz- vs. nevirapine-containing ART was 1.9 (95% CI 1.6, 2.4) using EMR data only and 3.2 (95%
CI 1.8, 5.7) when additionally using both chart review and interview validated data. Among efavirenz users, the aIRR
of pregnancy for depomedroxyprogesterone acetate (DMPA) vs. implant use was 1.8 (95% CI 1.5, 2.1) in EMR only
and 2.4 (95% CI 1.0, 6.1) using validated dataConclusion: Pregnancy rates are higher when contraceptive implants are concomitantly used with efavirenz containing ART, though rates were similar to leading alternative contraceptive methods such as DMPA. Our data
provides policymakers, program staff, and WLHIV greater confidence in guiding their decision-making around
contraceptive and ART options. Our novel, 3-phase validation sampling provides an innovative tool for using
routine EMR data to improve the robustness of data quality.