Some types of intravaginal practices (IVP) may increase the risk for HIV acquisition. This is particularly worrisome for populations with dual high prevalence of HIV and IVP. Women involved in transactional sex are at increased risk for HIV infection in sub-Saharan Africa. Social, cultural and economic influences are strong drivers of IVP in this population. To explore this, we carried out a qualitative research study to investigate the drivers and motivations for using IVP within a large observational study of women at high risk of HIV in Tanzania and Uganda from September 2008 to September 2009. Of the 201 women selected, 176 women took part in a semi-structured in-depth interview. Additionally, in Tanzania, eight focus group discussions among study participants and community members were carried out to obtain information on community norms and expectations. IVP were motivated by overlapping concerns with hygiene, morality, sexual pleasure, fertility, relationship security, and economic security. These motives were driven by the need to meet cultural and social expectations of womanhood, and at the same time attend to personal well-being. Among women involved in transactional sex in East Africa, interventions aimed at modifying or eliminating IVP should attend to local cultural and social norms as well as the individual as an agent of change.