The regular movement of the baby in the tummy is due to the twitching caused by hiccups while the baby is in the mother’s tummy. Since the baby’s diaphragm is relatively low, when the intestinal tract peristalsis touches the diaphragm, which causes the baby to hiccup; or when swallowing amniotic fluid, the stomach position increases, which also touches the diaphragm, which causes the baby to hiccup. When the baby hiccups, due to the imperfect development of the nerves in the brain, the limbs will twitch at the same time, so the pregnant woman will feel the baby’s rhythmic beating, which mostly occurs in the lower abdomen of the pregnant woman. The baby will also have such rhythmic hiccups after birth, which is a normal physiological phenomenon and nothing to worry about.