Introduction:
Transgenders (Hijras) are important population sub-group, which suffers from both inequality and inequity. They lack educational and employment opportunities rendering sex work an easy bread-winning option. The prevalence of unprotected sex among Hijras is high, though they have knowledge about its’ consequences. In this study, problem behavior theory (PBT) was used to determine risk factors leading to unprotected sex among this vulnerable population. Frequency of unprotected sex among Hijras was estimated, and risk factors for unprotected sex and its’ association with PBT variables were assessed.

Material and methods:
Data of 150 Hijras residing in Rawalpindi, Pakistan were used for this cross-sectional study. Data collection tool applied was developed based on AHDQ employed in problem behavior theory studies. Descriptive statistics that characterized Hijras were based on their age, education, mode of income, and monthly income. Binary logistic regression was performed to find association between unprotected sex and problem behavior theory variables.

Results:
Most (84.1%) of the respondents reported having unprotected sex, while fewer (71.0%) did not use a condom during their last sexual act. A positive correlation was observed between unprotected sex and parental control (OR = 1.907), while a negative correlation was observed between unprotected sex and parental support (OR = 0.919).

Conclusions:
The prevalence of unprotected sex among HSWs residing in Rawalpindi is high, despite them having knowledge about HIV and its prevention methods. The parental control and parental support are associated with condom use in last sexual act.