It looks like the most important vitamins that mommys to be should be sure to get enough of are B12, and folic acid... I found this multi for vegans:
We are also looking into having a natural, at home, water-birth, if when we get pregnant I am not in risk of any complications. Water birth is growing in popularity and more suited for the comfort of the mother and baby, putting them in a warm, relaxing bath that soothes muscles and the body while relieving tension and stresses that make childbirth more painful and a longer process.
Water birth resources here:
Here's a video that I find incredibly beautiful and inspiring
(though perhaps graphic, so you are warned):
We're getting excited with our potential prospects for a baby in the coming year or two! Look at all these cuties!