Hay, nausea and stomach ache with prenatal vitamins ay common talaga, especially sa early pregnancy, kaya hindi ka lang, a few of my mum friends nag-complain din about Obimin Plus, lalo na pagka-empty ang tummy. Try taking it with food or right after dinner, and if it still doesn't settle, best to chat with your OB about it because baka kailangan mo ng different brand or timing na mas okay sa iyo, some moms switch to other prenatals lang if ang side effects ay nakakaabala talaga. Hang in there, mom!