How effective are membrane sweeps?

Question

i.e. how often does labour follow

and how long after?

Also are they best done before or after a show?

Thanks

Answer 1

Why is this in garden & landscape?  Ahaha I thought it was going to be about those membranes which stop weeds growing!  

ETA Yes sorry I couldn't be of more help,  I don't think I'd be any help if your question WAS about those weed membranes either :)

Answer 2

well when i had mine by the time i got home i had a show, 2 days later i started contractions and my baby was born the day after that!