Motivations of pregnant women initiating HIV PrEP within antenatal care enrolled in a randomized trial to improve adherence in Western Kenya

Abstract

AbstractVertical HIV transmission remains a significant public health challenge in high-burden settings, where maternal HIV infection during pregnancy and breastfeeding account for nearly one-third of new paediatric infections. HIV incidence doubles during the perinatal period due to biological vulnerability and ongoing behavioral risks, including partners of unknown or positive HIV status. The World Health Organization recommends HIV PrEP for pregnant and postpartum women at substantial HIV risk. HIV PrEP delivery is increasingly integrated into routine maternal and child health (MCH) services, however real-world factors influencing pregnant women's decisions to initiate PrEP remain poorly understood. We conducted a cross-sectional secondary analysis of baseline data from the mWACh-PrEP study, a randomized trial among HIV-negative, PrEP-naïve pregnant women between 24-32 weeks gestation at five public MCH clinics in western Kenya who elected to initiate PrEP. Data on demographics, pregnancy history, HIV risk perception, partner characteristics, psychosocial factors, and PrEP attitudes were collected via structured electronic questionnaires. Poisson regression was used to examine associations between participant characteristics and high self-perceived HIV risk and PrEP initiation motivations. Among 600 women enrolled, 36.3% reported high HIV risk perception at PrEP initiation. High self-perceived risk was associated with having more than three lifetime sexual partners (aRR 1.43), high empiric HIV risk scores (aRR 1.70), experience of intimate partner violence (IPV) (aRR 1.92), and anxiety symptoms (aRR 2.23). Conversely, participants with high self-efficacy for daily pill-taking were less likely to have high risk perception (aRR 0.63). Women with unplanned pregnancies were more likely than those with planned pregnancies to report initiating PrEP due to concerns that their partner had multiple sexual partners (44.4% vs. 32.4%; aPR 0.80; 95% CI: 0.72–0.89) and feeling at risk for HIV (44.7% vs. 32.6%; aPR 0.86; 95% CI: 0.78–0.95) Women who experienced intimate partner violence (IPV) were more likely than those without IPV histories to report initiating PrEP due to concerns that their partner had other sexual partners (66.6% vs. 38.3%; aPR 1.27; 95% CI: 1.05–1.54) and to protect their infants from HIV (77.8% vs. 49.8%; aPR 1.32; 95% CI: 1.16–1.49). Pregnant women's decision to initiate HIV PrEP is influenced by a combination of behavioral risk factors (e.g., multiple lifetime sexual partners, condomless sex), psychosocial stressors (including IPV and anxiety), and pregnancy-specific contexts (notably unplanned pregnancies). Tailored HIV risk counseling that addresses discordance between objective risk and subjective perception, routine IPV screening, and integrated supportive services within MCH settings are critical to improving PrEP uptake and adherence and ultimately reducing maternal HIV acquisition and vertical transmission in high-risk settings