Quoting Frazier Aylia:" I. Have had two children and one on the way and i have never herd of this what is it and y do u do it?"
Being checked for dilation is when a doctor inserts two fingers and measures if your cervix has opened at all.
Effacement is how thinned out your cervix has become
Having your membrane swept, is when a doctor inserts their fingers inside you just as if they were to do an exam, and put a finger in your cervix and seperate the cervix from the babies sac. it is supposed to help speed up labor if your body is ready for it.
it sounds wayyy more painful than it actually is in my opinion, but I feel like theres no harm in getting it done.. like OP said, if your body is ready it'll help labor, if not it wont. no harm done.
hope i helped.