HIV retesting during pregnancy and postpartum is critical to reduce mother-to-child HIV transmission (MTCT) due to incident maternal infections. However, widespread scale-up of this policy may confer additional strain on health systems. HIV self-testing may be an innovative solution for maternal retesting by addressing client access barriers and staffing shortages.
HIV-negative pregnant women were enrolled between November 2017 and August 2018 in Nyanza and Nairobi regions in Kenya. At enrollment, retesting preferences were assessed for location (clinic or home), test type (saliva- or blood-based rapid), and test performer (self or provider). Reasons for preferences were assessed and women were asked to select a test strategy for retesting during the current pregnancy: blood-based testing by a provider in clinic (clinic-based testing [CBT]) or self-testing at home using a saliva-based test (home-based testing [HBT]). Chi-squared and t-tests were used to compare reasons for choice. Generalized linear models (log link, binomial family) were used to assess cofactors for testing strategy.
Overall, 1,000 pregnant women were enrolled, with a median gestational age of 28 weeks (Interquartile range [IQR]: 22-32) and median age 24 years (IQR: 21-27). More women elected CBT (665 [67%]) than HBT (335 [34%]) for retesting (p<0.001). Later gestational age was associated with lower likelihood of electing HBT (PR per week: 0.99, 95%CI: 0.98-1.0, p=0.04). Maternal age, parity, income, education, same day HIV testing, marital status, relationship duration, and partner testing history were not associated with choice (p>0.05 for all). Preferences for test location (33% home vs 67% clinic), test operator (31% self vs 69% provider), and test type (32% saliva vs 68% blood) mirrored choice of HBT or CBT. Women who elected HBT were more likely to report being unavailable during clinic hours than women who elected CBT (18% vs 10%, p<0.001) and report longer clinic wait times (73 vs 53 minutes, p<0.001).
While pregnant women generally preferred CBT for HIV retesting, HIV self-testing at home was preferred by one-third of women, particularly those with challenges accessing health centers. As HIV retesting scales up in pregnancy and postpartum, HBT may reduce burden on health systems, increase retesting rates, and facilitate efforts to eliminate MTCT.