Pregnant women often stay up late, may increase the risk of miscarriage, cause fetal development delay, affect the physical quality of the fetus after birth, etc.. 1. Increase the risk of miscarriage: pregnant women often stay up late, will make pregnant women’s hypothalamus – pituitary – gonadal axis interference, resulting in hormonal disorders in the body, long-term will increase the risk of miscarriage. 2. Fetal development retardation: During the sleeping period, the pregnant woman’s body will secrete some hormones to promote fetal growth and development, such as growth hormone, thyroxine and so on. If pregnant women often stay up late, it will reduce the secretion of these hormones, which will cause the development of fetal bones and nervous system to be delayed. 3. Affecting the physical quality of the fetus after birth: during the mother’s sleep, the body will secrete some antibodies, which enter the fetus through the placental barrier. If you often stay up late, the antibody production is insufficient, the fetus is easy to be born by a variety of bacterial infestation, the emergence of neonatal pneumonia and other infectious diseases. Note: Pregnant women should not stay up late, have a regular routine and take regular checkups.