Simple or complex hyperplasia?  With or without atypia?  More information would be helpful (which is why they did the biopsy).. . Progesterone treatment is the best option except for when atypia is present, although it can be used (and is sucessful in 2/3 of cases, thus avoiding the need for a hysterectomy, but you would need periodic biopsies to watch for additional atypia).. . Side effects of progesterone treatment can vary from woman to woman.  Some may gain a little weight, others may develop depression.  Many do not notice anything except being a little more tired than normal. There is an increased risk of blood clots, especially if your are obese and smoking. Your doctor should explain what possible side effects there can be so that your treatment can be altered or stopped if needed.