The causes of insomnia at night in the 7th month of pregnancy are usually considered hormone level change, uterus enlargement, diet change, calcium deficiency, frequent urination, and sleep environment factors. Specific analysis: 1, hormone level change: pregnant women are more sensitive mentally and psychologically after pregnancy, and their tolerance for stress will be reduced, so their emotions are not very stable during this period, and symptoms such as depression and insomnia often occur; 2, uterus enlargement: pressure on the stomach and heart area, causing physical discomfort and insomnia; 3, diet habit change: some pregnant women have great changes in taste during pregnancy, especially the saturated fatty acids in food. Fatty acids, will change the body’s hormone secretion, resulting in many physical symptoms, such as insomnia; 4, lack of calcium: calcium deficiency leads to leg cramps and insomnia; 5, frequent urination: the uterus increases pressure on the bladder, resulting in the symptoms of frequent urination and insomnia; 6, sleep environment: too noisy, affecting sleep, resulting in insomnia. Pregnant women can take appropriate calcium supplements during pregnancy, relax, avoid excessive stress and mood swings, eat a light diet and drink as little water as possible before bedtime.