I looked at that when i was pg and was going to make it if i became overdue, MJ came on her due date so i never had the chance.
I have read that loads of herbs can play a role in the onset of labour, so it may be this aswell.

I love eggplant so should cook this anyway, really wanted to cook it when i was pg but was to scared that i would bring on early labour.
Sorry, i havent been any help, but IMO if the recipe sounds appealing to you and you are overdue, why not try it, it is worth a shot and cant do any harm