last pregnancy i was traveling all the time and eating maca, cacao, coconut, and loads of other foods i had learned about but never eaten before. i stopped eating aloe, but drank kombucha and though my diet was far from vegan, incorporated many whole food supplements in during the entire pregnancy.
she's beautiful. she was late, 8lbs 8oz, 22 1/2 inches long, born at home after a 12 hour labor, and has been the most amazing baby. I have no fear of consuming maca in small amounts during pregnancy. have again occasionally during this pregnancy. I'm on my 4th. maca was a great smoothie addition in first trimester for me, and 3rd, and i added it to my homemade raw power bars. i'm not a dedicated raw foodist, but have definitely a big raw foodie streak in me, and the maca/cacao/vanilla desserts are hugely popular in my world!
did not find a whole lot of info except that maca was food for the Incans, and that animals and people consumed it for trace minerals especially to support fertility. so figured it didn't hurt too much, in normal food doses.
just my personal experience!