Maca root is like a "yam" or "sweet potato" it grows in the ground and looks pretty much exactly like it's cousin the yam. It is a main food source for (some of) the people in Peru, Indes mountains and is also considered a natural fertility booster as it contains phyto-progesterone.
Wild yam also has the same properties
(I used to work in Health & Natural foods for 11-12 years off/on)
Chaste tree berry (vitex) is something that also helps balance hormones along with Evening Primrose oil.... there's a tincture called "vitex elixer" that might be helpful *if* you have a hormonal imbalance... it's geared towards the luteal phase

here's a link.... I've been recommended this and have recommended it from my own experiences. Also I've taken wild yam, evening primrose, and some other things too
Gaia Herbs: Vitex Elixir for Women (product)
Here is an AWESOME BOOK!!! Wise Woman's Herbal for the Childbearing Year
Wise Woman's Herbal for the Childbearing Year... Author: Susan Weed