TUESDAY, Feb. 3, 2026 (HealthDay News) -- Postmenopausal women who used hormone therapy lost significantly more weight while taking tirzepatide than women only taking tirzepatide, according to a study published online Jan. 22 in The Lancet Obstetrics, Gynaecology, & Women’s Health.Regina Castaneda, M.D., from the Mayo Clinic in Jacksonville, Florida, and colleagues evaluated whether use of hormone therapy enhances weight loss and cardiometabolic response to tirzepatide (≥12 months) in postmenopausal women with overweight and an adiposity-related comorbidity or obesity. The analysis included 120 postmenopausal women with body mass index ≥27 kg/m2 (40 using hormone therapy and 80 matched women not using hormone therapy).The researchers found that the hormone therapy group lost a greater percentage of body weight at last follow-up than the group not receiving hormone therapy (–19.2 versus –14.0 percent). Similarly, a higher proportion of women in the hormone therapy group reached a total percentage body-weight change of ≥20 percent, ≥25 percent, and ≥30 percent. Improvements in glycemia, blood pressure, and concentration of liver enzymes were seen in both groups. Additional reductions in diastolic blood pressure and concentrations of triglycerides and aspartate aminotransferase were seen in women using hormone therapy."The magnitude of this difference warrants future studies that could help clarify how GLP-1-based obesity medications and menopausal hormone therapy may interact. Interestingly, preclinical data suggest a potential synergy, with estrogen appearing to enhance the appetite-suppressing effects of GLP-1," Castaneda said in a statement.Several authors disclosed ties to the pharmaceutical industry.Abstract/Full Text (subscription or payment may be required).Sign up for our weekly HealthDay newsletter