Purpose This study explores women's experiences of a novel prehabilitation intervention, integrating early vaginal dilator therapy before and during pelvic radiotherapy. Methods This qualitative study included sixteen women scheduled for pelvic radiotherapy. All participants received a pre-treatment intervention with individualized information and support to start vaginal dilator therapy prior to radiotherapy. Semi-structured interviews were conducted with all sixteen women before or during treatment. Of these, ten also participated in follow-up interviews after radiotherapy. Data were analyzed using reflexive thematic analysis. Results Four themes were constructed reflecting women's experiences of the new prehabilitation intervention: (1) Regaining control while facing the unknown, (2) Navigating identity, (3) Conceptualizing vaginal and sexual health, and (4) Building trust. Women found that vaginal dilator therapy during prehabilitation enabled a sense of control and readiness for upcoming sexual and vaginal health concerns. The early support was perceived as timely, acceptable, and empowering, regardless of women's initial motivation to engage. None of the women preferred to only receive the information after treatment, reflecting the value of proactive care . Conclusion Integrating vaginal dilator therapy into prehabilitation may enhance preparedness, promote self-care, and reduce distress during pelvic radiotherapy. Further research is needed to confirm benefits and tailor support to individual needs.