This study aims to see if **triptorelin** can help protect the **ovaries** of young women with cancer who are getting chemotherapy. **Chemotherapy** is a treatment for cancer that can sometimes harm the ovaries, making it hard to have babies in the future. Triptorelin is a medicine that can pause the ovaries' work for about six months, possibly protecting them from damage. **Key Points:** - **Study Length:** The study lasts up to 2 years, with follow-ups at 1 and 2 years. - **Procedure:** Some participants will receive a shot of triptorelin and others will not. Everyone will have blood tests. - **Eligibility:** Females under 40, except those with breast cancer, who are starting chemotherapy. To join, you must sign a consent form and meet certain health criteria. If you’re pregnant or breastfeeding, you can’t participate. Participants should also use effective birth control during the study. There is no mention of compensation, but it's important to discuss any risks and benefits with your doctor.