I am 36 weeks and 4 days, and have taken the exact same prenatal vitamin this entire pregnancy and up until about a month to two months ago, I was taking them fine without a problem. Now I feel nauseous whenever I take them. If you haven't yet, try taking them after you eat a meal. It helps having something in your stomach. If you've tried to take them when you have food in your stomach and that isn't helping, try to take tums after you take the vitamin.