36th Wks

Hi, I am in my 36th weeks and just had my routine check with gynae today. Gynae told me that my baby is on the bigger side and was shocked that baby gained almost 1kg from last month's check. (baby is approx 3kg now). She advised me to control my diet but problem is, i keep getting hungry. I'm kinda afraid to have snacks now like i usually do and is worried that I might not be able to have normal vaginal birth. Any advices?