Findings on access to general healthcare for transgender people have emerged, but little is known about access to transition-related medical care for transwomen (i.e., hormones, breast augmentation, and genital surgery). Transgender women have low access to general medical care and are disproportionately at risk for substance use, mental illness, and HIV. We conducted an analysis to determine if utilization of transition-related medical care is a protective factor for health risks to transgender women and to investigate if care differs by important demographic factors and HIV status. A secondary analysis was conducted using data from a 2010 HIV surveillance study using respondent-driven sampling to recruit 314 transwomen in San Francisco. Survey-corrected logistic regression models were used to estimate odds ratios for six psychosocial health problems-binge drinking, injection drug use, anxiety, depression, suicidal ideation, and high-risk intercourse-comparing various levels of utilization of transition-related medical care. Odds ratios were also calculated to determine if utilization of transition-related medical care was related to less overlap of risk domains. We found that Latina and African American transwomen had significantly lower estimated utilization of breast augmentation and genital surgery, as did transwomen who identified as transgender rather than female. Overall, utilization of transition-related medical care was associated with significantly lower estimated odds of suicidal ideation, binge drinking, and non-injection drug use. Findings suggest that utilization of transition-related medical care may reduce risk for mental health problems, especially suicidal ideation, and substance use among transwomen. Yet, important racial/ethnic and gender identity disparities in utilization of transition-related medical care need to be addressed.