Fetal movement in the fifth month of pregnancy may be caused by physiological factors, trauma, hypoxia and other factors. 1. Physiological factors: a large amount of food containing high sugar content, pregnant women’s mental stress, physical overwork and other factors, may lead to frequent fetal movement, and also in the lower part of the stomach, is a normal physiological performance. 2. Trauma: when you are pregnant for more than five months, the abdomen has been hit violently, which will also make the fetus move suddenly and frequently, you should rest reasonably and observe whether there are other abnormal manifestations. 3. hypoxia: placenta praevia or acute fetal distress may lead to intrauterine oxygen deprivation, which can cause sudden and frequent fetal movements that last for a long time. If you are pregnant for more than five months and there are other abnormalities, you should go to the obstetrics and gynecology department of the hospital for a detailed examination and treatment to avoid any adverse effects.