@mariam58, I moved your question about estradiol vaginal inserts while on an aromatase inhibitor (Letrozole) to this active discussion so you can connect with others.
- Estradiol for vaginal atrophy after breast cancer. Is it safe? https://connect.mayoclinic.org/discussion/estradiol-for-vaginal-atrophy-after-breast-cancer-is-it-safe/

Weighing the pros and cons, understanding risk vs quality of life make decisions hard. Reading how other women have informed themselves, the criteria they used to decide can be helpful. I hope that this discussion will give you more information to have a well-informed discussion with your oncologist.