In Cambodia, young women from rural areas come to live in Phnom Penh, the capital city, in order to find an activity able to meet their needs and those of their families. Among them, many are those who find an activity as a hostess bar karaoke. This activity induced physical and social changes, for these young women and tends to modify their relation to their femininity, their sexuality and their health. Considered by public health actors as “vulnerable populations” because of their activity as sex worker, these women are sometimes targeted for prevention and care activities in reproductive health. This contribution approaches certain aspects of the construction of health policies in the context of sex trade in Cambodia. Furthermore, the article seeks to explore how these young women deal with their new role and how they implement or negotiate care practices related to HIV prevention and unwanted pregnancies. The issues raised highlight how social and spatial migrations of women observed in Cambodia induce “unprecedented” practices in reproductive health as well as new forms of construction of gender identity and female body. Beyond that, this contribution proposes to revisit the concept of “sexual economic exchange” in the Cambodian context.