The Caress study is a single-center, open-label, randomized controlled trial (RCT) evaluating the efficacy of a combined treatment using topical hyaluronic acid and high-concentration oxygen therapy (Vaginal Natural Oxygenation Device - VNOD) in improving symptoms of Genitourinary Syndrome of Menopause (GSM) in postmenopausal women, including those with a history of breast cancer. The primary objective is to assess vaginal dryness improvement one month after treatment, comparing two groups: an experimental group receiving VNOD therapy with hyaluronic acid and a control group using a hyaluronic acid-based gel (Hydeal-D®). Secondary endpoints include the evaluation of additional vaginal symptoms (pain, irritation, itching, sexual health, quality of life) up to six months post-treatment. The study will enroll 80 women (40 with a history of breast cancer and 40 without). Statistical analysis will use chi-square tests and logistic regression to compare symptom severity reduction between the two groups. With a duration of 18 months, the study aims to provide an innovative, non-hormonal treatment option to improve the quality of life for postmenopausal women, particularly those with a history of breast cancer