Doc says no to epo

I've had a completely low risk pregnancy. Currently 36 weeks and I asked my doctor if i could start inserting evening primrose oil and she said no, that she doesn't want anything put up there. But says i can have sex.? Ive read so many other women benefiting from epo and that their doctors and midwives actually suggest it. Im going to listen to her ofcourse I just don't get why other doctors suggest it then. Im 3 cm and 60% thinned out as of today