Ay sis, 33 weeks na! That's a lot of diarrhea every hour, definitely check with your OB kaagad kasi at that stage of pregnancy, dehydration can be risky, lalo na kung tubig talaga ang labas. A few of us had this and it turned out iba-iba ang cause, isa namin was food sensitivity, isa naman possible infection na kailangan talaga ng doctor, so it's really best na ma-assess siya ngayon. In the meantime, sip on clear fluids, coconut water, or electrolyte drinks to stay hydrated, pero please don't delay calling your OB ha!