Partnership dynamics and dual method use among adolescent girls and young women in South Africa: a longitudinal analysis of HIV Prevention Trials Network 068 data

BACKGROUND: In South Africa, adolescent girls and young women (AGYW) account for nearly 28% of all new HIV infections and 65% report an unintended pregnancy before age 25. Dual method use is known as the most reliable protection against pregnancy and sexually transmitted infections, including HIV. However, uptake of dual method use remains low. Understanding how partner characteristics and dynamics impact AGYW dual method use might explain low uptake beyond individual and environmental factors.
METHODS: Data are from HIV Prevention Trials Network (HPTN) 068, a longitudinal study of AGYW (age 13-23) in South Africa. We used GEE log-binomial regression models to calculate adjusted risk ratios for the association between partner characteristics, partnership dynamics and dual method use. Partner characteristics included being > 5 years older, concurrent partnerships, HIV status, and provision of financial support. Partnership dynamics included relationship power, gender equitable norms, intimate partner violence (IPV), and condom use communication. Dual method use was defined as concurrent hormonal method and condom use.
RESULTS: Our sample included 2,452 HIV-negative AGYW who were followed for up to five years. At baseline, most participants reported that it was very important to not be pregnant (N = 1520, 62%) and that they had no chance of getting HIV in their lifetime (N = 1795, 73%). Among sexually active participants (N=650, 27%), 10% (N = 64) were using only condoms, 20% (N= 133) only hormonal methods, and 13% (N = 87) both methods. At endline, 1439 (90%) participants were sexually active and 5% (N = 70) were using only condoms, 17% (N= 247) only hormonal methods, and 10% (N = 144) both methods. After controlling for pregnancy intention and covariates, we found knowing a partner's HIV-positive status (aRR: 1.48, 95% CI: 1.13, 1.93), high relationship power (aRR: 1.48, 95% CI: 1.08, 2.19), and experiencing no IPV in the past year (aRR: 1.22, 95% CI: 1.03, 2.44) to predict dual method use.
CONCLUSIONS: Partner characteristics and dynamics are important for dual method use among AGYW. Interventions to help AGYW navigate partnership dynamics and safely engage partners in HIV status disclosure could be beneficial for both HIV and pregnancy prevention.