[Spero Mcgee]

I'm guessing gaining weight naturally or pregnancy works like a charm. Although gaining weight is generally speaking something women avoid though.
I doubt that multiple pregnancies is desireable though unless you are intending to have alot of children, however perhaps http://en.wikipedia.org/wiki/Surrogacy as explained there might also be something? Inducing lactation might also be something.
These are just things I read or heard from the net, so take these ideas with a pinch of salt.