The tightness and hardness of the stomach at 36 weeks may be caused by pseudo uterine contractions, uterine enlargement and compression, or uterine stimulation, which can be relieved by proper rest, changing the body position, and reducing stimulation. 1. Pseudo uterine contractions: 36 weeks of the stomach simply tight and hard, the duration of a relatively short period of time, the interval is relatively long, without the accompanying symptoms of pain, is considered to be pseudo uterine contractions, women should pay more attention to bed rest, minimize the activities, the more frequent pseudo uterine contractions can go to the hospital to keep the baby treatment, the use of magnesium sulfate to inhibit the contraction of the uterus. 2. uterine enlargement compression: 36 weeks of pregnancy belongs to the late stage of pregnancy, the uterus increases significantly, so that the ligaments around the uterus is stretched, taut, tension, will not feel the stomach tight and hard, you can appropriately change the posture of the lying down, such as the left side of the lying down position to alleviate the symptoms. 3. uterine stimulation: 36 weeks pregnant usually walk too much, a large amount of activity, eat stimulating food caused by gastrointestinal spasms, can also cause the stomach tight and hard, usually to reduce walking, reduce the amount of activity, eat light food, may improve the symptoms. If you feel abnormal discomfort during 36 weeks of pregnancy, you should seek medical examination and treatment in time.