In the fourth month, your baby’s head and body size are balanced. His face now looks more human. His eyes move from the sides of his head to the front of his face. As of this month, your baby also develops reflexes. He will be moving frequently in your womb during these months; in fact, if you press gently on your stomach, your baby may respond, but it may still be too early to feel it.
During these months, your bump might become more visible. But even if your bump isn’t very big, you may still be gaining weight and you should wear loose, comfortable clothes. You are likely to suffer heartburn at this time. This is because, during pregnancy, the placenta produces high levels of progesterone, which softens the valve between the stomach and gullet. Gastric acid can therefore leak back into the gullet, especially when you lie down, and cause an uncomfortable burning sensation.