The UNFPA 2022 State of the World Population (SWOP) report recognises that certain populations of young women and girls are at a higher risk of unintended pregnancy, but did not adequately address the grave situation of female sex workers (FSWs), who experience the worst sexual and reproductive health outcomes, especially during humanitarian crises. This study assesses the risks of unintended pregnancy among FSWs and sex worker organizations? response during the stringent COVID-19 containment measures in East and Southern Africa (ESA). A mixed-methods approach consisting of a desk review, key informant interviews and an online survey was used for data collection. Key informants and survey respondents included representatives of sex worker-led organisations and networks, organisations providing services to sex workers, development partners, advocacy organisations and donors, with priority given to key informants who had direct experience of providing services to sex workers during the COVID-19 pandemic. In total, 21 key informants were interviewed and 69 respondents participated in the online survey, with representation from 14 out of 23 countries in the ESA region.The study findings show that the disruption to livelihoods and threats to human rights occasioned by the stringent COVID-19 containment measures intersected with sex workers' access to contraception and risk of unintended pregnancy. Looking to the uncertain future of humanitarian crises, the study concludes by outlining critical issues that need to be addressed to ensure resilience of SRHR services for populations in vulnerable positions, such as sex workers.