A friend gave me a piece of polished rose quartz when I'd been TTC for a while - it's supposed to enhance fertility. I don't think it worked (or it took about a year to kick in ), but I was touched by the gesture all the same.
It says the Rose Quartz is for restoring the balance to the emotions and hormones.
The Moonstone was for the fertility. So maybe a moonstone might have worked better.
I e-mailed her and asked her, and she said it is a combination of all the stones that make it work. Sounds good to me