1, weight: 2-4 days after birth because of the intake of less and more water excretion, so the weight of the anti-birth decline, but generally not more than 10%, such as the decline of too much, the cause should be analyzed. After gradually rebound, 1 week after the level of up to the birth. 2, breathing: there is spontaneous breathing, but more superficial and irregular. Frequency is fast, generally 40-60 times / min, 2 days after birth down to 20-40 times / min. 3, heart rate: 120-140 beats / min, fluctuating, and then gradually slowed down to 120 beats / min. 4, digestion: the intestinal tract area is relatively long, the absorption area is larger, so it can adapt to the absorption of a large amount of liquid food. The pancreatic sphincter is weak while the pyloric sphincter is tense, and the stomach volume is small, so overflow is easy to occur. Newborns because the liver glycogen stores are not much, so within 1 hour after birth should start feeding milk or sugar water. 12 hours to discharge dark green sticky fetal stool, 2-3 days after the transition to yellow soft stool, if 24 hours later still do not defecate, should be traced to the cause. 5, urination: after birth that can urinate, urine is clear, 7-10 times a day. If you still do not urinate after 24 hours, the cause should be traced. 6. Immunity: Because of certain antibodies and immunoglobulins obtained from the mother, there is passive immunity to rubella, measles, scarlet fever and diphtheria within 6 months of birth, so they will not suffer from these diseases. But the lack of immunoglobulin synthesis ability, so the poor defense against other infections, the disease is easy to spread, making the disease worse. 7. Sleep: 20 hours per day and night on average, except for feeding and diaper changing, almost all of them are in sleep. If the baby cries a lot, the cause should be traced. 8.Other: There are reflexes such as sucking, swallowing, hugging and holding; hearing and smell senses are weak; there are responses to light; touch and temperature senses are sensitive, and pain senses are dull. The brain is not fully developed, so there are uncoordinated or involuntary movements.