fetal heart rate Doppler

My Baby boy was still born at 34 weeks due to umbillical cord being tightly wrapped around his neck. Went to the hospital after not feeling him for a day and they found no heart beat. When they took me to the room where I would deliver 36 hours later, one of the nurses said that I should get a heart Doppler to put my mind at ease. I was also told that sometimes insurense will cover them if prescribed by a doctor. I don't mind paying for one, but if I don't have to I don't want to buy one when I can get one for free. Has anyone been prescribed a heart Doppler and insurense cover it? I'm going to talk to my doctor (who said I would be high risk during my next pregnancy) at my first ultrasound and see what I can do. Has anyone been in a situation like this?