Nausea during prenatal period is not necessarily a sign of an impending birth. First of all, nausea during labor may be caused by eating irritating food, smelling irritating smells or pressure on the gastrointestinal tract. The symptoms of preterm labor usually include bleeding from the vagina, frequent abdominal pain due to regular contractions, and sudden rupture of amniotic fluid. This shows that nausea during the prenatal period is not necessarily related to the imminent birth, not necessarily nausea is the imminent birth.