7.5cm ovarian dermoid cyst has been growing steadily. doctor says to wait and re-evaluate in another 6 months. is that safe? is surgery more risky as the cyst gets larger?

Second opinion: Hard to know, as there are multiple unknowns for your case. However, it is always okay to get a second opinion. Your regular doc will help you. Take a family or friend with you and ask questions, take notes. You will learn a lot and be better able to make informed decision about your care. Be well.

.: A dermoid cyst is unlikely to regress. If they grow too big then the surgery would be more difficult to just resect the cyst, and the surgery might involve the ovary. It's also good to get a pathology diagnosis since you are 39. So i say talk to your doctor about surgery.