Will they strip my membranes? ?

I am 38 weeks pregnant and on my next appoint I will be 2 days away from 39 weeks. I am wondering if I ask for my doctor to strip my membranes if she would or not. I had an ultra sound at 36 weeks which showed that my baby was 6 pounds 10 ounces, I have read that a baby can gain a rather large amount in the last 4 weeks of a pregnancy. I'm scared that if I'm allowed to go any longer then this that I will have a very large baby and be forced into a c-section. I didn't know if they would advise against this or not. Any input is greatly appreciated. Thanks!