This study looks at how a medication called relugolix combination tablet affects bones over time in women with uterine fibroids or endometriosis. Uterine fibroids are non-cancerous growths in the uterus that can cause heavy periods, and endometriosis is a painful condition where tissue similar to the lining of the uterus grows outside it. The study will last for 4 years, with follow-ups for 1 year after stopping the medication. Up to 1000 women will take part, and bone health will be checked every 6 months using a special X-ray called DXA.

• This study lasts for 4 years with a 1-year follow-up.
• Participants will visit the clinic every 6 months for bone checks.
• Only women aged 18-50 with specific health conditions can join.

Women who join must not plan to become pregnant during the study and need to be in good health. There are some health conditions and previous treatments that may prevent joining the study. This study helps researchers learn more about the long-term effects of the medication on bone health in women with these conditions.