I've been told there is no point unless your cervix has already started to soften, as the hormones & chemicals released help to speed up labour by further softening the cervix not start labour.

Might be some merit in being on top in an upright position to bring on labour, or on all fours any position that is good for envouraging bubs to move down.

Frankly right now (my due date was 27th) I couldn't be.... well you know