Honestly I don't know the answer to your question but the nights that I do remember to take my prenatal vitamin. I tend to wake up in the middle of the night so hungry. When I forget to take it those nights I normally am ok without having to get up to eat something. So maybe there is something to do with that all. But not really sure either.
That's what I'm saying... Before taking them I would only eat like two times a day, I normally weigh 105 lbs but now that I've started taking them, I've gained a little bit of weight and starving like every two hours.... And I'm not pregnant right now. Maybe it does have something to do with it, but who knows?