I started getting checked a day before I was 39 weeks
My doctor said they will offer to check me at my 37 week appointment ( so next week ) otherwise they don't check until you hit 40 weeks , But I also have a Midwife CNM
They never checked me til I was overdue. I didn't want them playing in there anyways plus I hear,lots of women say they were at 2 cm for Weeks sometimes. Everyone is different.
Im 35 weeks tomorrow and I am getting checked at 36 weeks and then weekly ill be getting checked
My doctor didnt check me until my 39 week appointment. I think it all depends on your doctor though. Just remember too that being dilated and effaced does not necessarily mean that labour is imminent ...ive been 3 cm dilated and 70 % effaced for the past week (im overdue now) and I think it was worse knowing because I expected to have my LO by now :( Good luck to you though!!! Hopefully your appointment goes well and you get the answers you are looking for :)
Are you in the U.S. Because here usually if you asked the doctor they'll do it for you. From what I here other places won't do it til you're overdue.