Most moms-to-be go from innies to outies in the second or third trimester. It happens because your expanding uterus puts pressure on the rest of your abdomen, pushing your belly button outward. After you deliver, the pressure will be gone, and your belly button will go back to normal. If your belly button starts to become irritated from rubbing against your clothing, try wearing maternity pants with a soft, breathable panel (we know you hate them, but they're made this way for a reason). You can also try pairing loose, flowy shirts with low-rise pants that leave your navel exposed. Although uncommon, sometimes a woman's belly button can protrude so much that it's considered an umbilical hernia. Your doctor should notice this during one of your routine prenatal visits and should be able to gently nudge it back. In very rare instances, an umbilical hernia may require minor surgery to repair.