38 weeks with my first . 2cm dilated and 50% effaced, feeling slightly nauseous with regular contractions that aren't painful. when will she be here?

Difficult to predict: It could be any day, but some women have cervical change consistent with what you describe for days or even weeks before delivery. At this stage of pregnancy, every day that you remain pregnant is better for the baby. Although considered full term at 38 weeks, babies delivered at 39-40 weeks have been found to have fewer health problems. When contractions get painful, go to hospital. Good luck