Just like your gut, your vagina is home to all sorts of bacteria, says Dr. Streicher. The "good" kind, called lactobacilli, help keep vaginal pH between and . But if the vagina's pH is disrupted—say, from semen or menstrual blood—it may become less hospitable to lactobacilli and more welcoming to bad bacteria. The overgrowth often comes with a fishy odor as well as vaginal discharge and irritation. For women who notice a slight smell after sex or their period, using a pH balancing gel, like RepHresh, can make the vagina more acidic and help lactobacilli get the upper hand again. That said, if the bacterial imbalance turns into full-on BV (think: painful urination, itching, more discharge and odor), see your doc for an evaluation and treatment (possibly antibiotics).
Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes.