Testosterone and Vaginal Function

Introduction: Androgens have been shown to exert beneficial effects on vaginal physiology, at least partially independent of their aromatization to estrogens. Androgen deficiency in the vagina and in the other genitourinary tissues contributes to the development of vulvovaginal atrophy and genitourinary syndrome of menopause, resulting in impaired arousal and lubrication and dyspareunia. Objectives: To summarize the role of testosterone in modulating vaginal structure and function. Methods: A qualitative review of the relevant literature on the topic was performed using the PubMed database. We present a summary of preclinical and clinical evidence supporting the involvement of testosterone (T) in vaginal physiopathology and discuss it in terms of the role of the vagina in female sexual response. Results: Androgens are important in the differentiation of the vagina and in maintaining trophic and functional actions in postnatal life, as suggested by the detection of the androgen receptor and of the key enzymes involved in androgen synthesis. T is essential for the integrity of vaginal tissue structure (including non-vascular smooth muscle thickness and contractility and collagen fiber compactness) and for the complex neurovascular processes that regulate arousal and lubrication (vascular smooth muscle relaxation via the NO/cGMP/PDE5 pathway, nerve fiber density and neurotransmission). T has also been reported to modulate nociception, inflammation, and mucin secretion within the vagina. Available and potential androgen-based treatments for vulvovaginal atrophy/ genitourinary syndrome of menopause and for other conditions leading to female genital arousal disorder and dyspareunia are presented. Conclusions: The vagina is both an androgen-target and synthesis organ. Preclinical and clinical data consistently suggest that T plays an important role in maintaining vaginal health and genital sexual function.