Hi, I'm sorry you and your wife are going through this. The above poster is right, an ectopic pregnancy would need emergency surgery to keep the tube from rupturing. Most cysts over 5 cm are usually removed by surgical means. Push for your doctor to do something sooner rather than later. Prayers coming your way. Keep us posted!
I really hope it turns out to be a simple cyst. However, at 5 cm, even that is a candidate for surgical removal. I am surprised the doctor could not confirm this one way or the other a bit faster than this.
An ectopic pregnancy will mean immediate surgery before a dangerous rupture occurs.