The frequent fetal movement at night during the 38th week of pregnancy is usually a normal phenomenon during pregnancy, as the environment is quieter at night, the fetus is more active and the environment is less disturbed, the fetal movement is also easily detected. In addition, it may also be caused by other circumstances, and the cause can be determined according to the specific circumstances. 1, maternal factors: pregnant women at night after taking a bath or after eating, emotional ease, happy mood, may make the fetal fetal movement increase. In addition, if pregnant women drink coffee, strong tea and other drinks, it may increase fetal excitability and cause frequent fetal movements; 2, fetal factors: the frequency, rhythm and intensity of fetal movements vary from fetus to fetus, if the daily fetal movement count are more, and the fetal movement time stage is closer, it may belong to the fetal natural pattern; 3, pathological factors: in general, the number of fetal movements per hour is 3-5 times, if it exceeds normal value is abnormal fetal movement, need to consider the possibility of fetal intrauterine hypoxia. If the fetal heart sound is monitored and shows that the fetal heart sound is <120 beats/min or >160 beats/min, it is abnormal, in addition, fetal heart monitoring is needed, if the fetal heart monitoring indicates poor baseline variation, occasional or frequent decelerations, it may be a manifestation of fetal hypoxia, which needs to be actively treated to avoid serious consequences of fetal distress or even fetal death in utero.