Background Cross-sex hormone therapy (CHT) changes the physical characteristics of transgender women to match their gender identity and expression. This study aimed to determine the effects of feminizing cross-sex hormones on body composition, bone mineral density (BMD) and muscle strength in transgender women. Methods A prospective observational study assessed 11 participants who underwent feminizing CHT. Dual energy X-ray absorptiometry (DXA), and handgrip strength were measured before CHT and after 6-months of CHT. Fat mass, lean body mass (LBM), and BMD were measured by DXA and handgrip strength was measured by hand-dynamometer. Results Regional body fat in the trunk, legs, and gynoid region increased by 18%, 27.4%, and 27.2%, respectively after 6 months of CHT. Total body fat increased by 16.2%, while the fat mass ratio decreased by 7.2%. Although body fat increased, the android/gynoid fat ratio decreased; BMD in the lumbar spine significantly increased by 3.9% ( P =0.0051), but changes in the femoral neck ( P =0.1969) and total femur ( P =0.4769) were not significant. Changes in LBM ranged from −3% (trunk) to −8% (arm region). Right-hand grip strength also significantly decreased by 7.7% ( P =0.0467). Conclusions After 6 months of CHT, transgender women showed a general increase in fat mass and a decreased in overall LBM and handgrip strength. Increase in fat mass percentage were more remarkable in gynoid region, leading to a more “female” body fat distribution.

Bacterial vaginosis (BV) is the most common disease in women of childbearing age and is caused by the growth of abnormal microbiota in the vagina. Probiotic consumption can be an effective alternative treatment to preserve or improve vaginal health. In the present study, MED-01, a complex of five strains of probiotic candidates isolated from the vagina of Korean women, was used. This study was designed as a 12-week, randomized, multicenter, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of MED-01 on vaginal health. A total of 101 reproductive-aged women with a Nugent score of 4–6 took MED-01 (5.0 × 109 CFU) or a placebo once a day, and 76 participants completed the procedure. MED-01 significantly reduced the Nugent score compared with the placebo. Quantitative PCR analysis confirmed that Lactobacillus plantarum was significantly increased in the vagina, whereas harmful bacteria such as Mobiluncus spp., Gardnerella vaginalis, and Atopobium vaginae were suppressed after 12 weeks of MED-01 ingestion. No adverse events to the test food supplements were observed in the participants. These results confirmed that MED-01 can be used as a probiotic for treating BV, as it improves the vaginal microbiota.

Recently, gender-affirming hormone therapy for gender incongruence has become an issue in various countries and organizations with various guidelines. In South Korea, several clinical treatments are also used with many possible options. These treatments include masculinizing (female-to-male [FTM]) or feminizing (male-to-female [MTF]) hormone therapies, with regimens usually driven by standards of hormonal replacement therapy for hypogonadism (i.e., hypogonadal natal men and postmenopausal women). This cross-sex hormone therapy can change patients’ physical appearance to better match their gender identity and expression. Regarding masculinizing therapy, injection and transdermal gel types of testosterone are used according to international guidelines. Progesterone is utilized in the form of oral pills, injections, or intrauterine devices to suppress menstruation and avoid pregnancy. Essentially, feminizing therapy uses androgen blockers along with estrogen. This is because estrogen alone cannot exert sufficient androgen-suppressing effects. In South Korea, the most commonly used androgen blockers are spironolactone and cyproterone acetate. Gonadotropin-releasing hormone (GnRH) agonist is also available. Regarding estrogen, oral pills, injections, and transdermal gels are utilized. This review introduces these gender-affirming hormone therapies in South Korea and discusses the side effects of each regimen.