The enlarged uterus can be felt clinically in the abdomen only after the third trimester of pregnancy. If the uterus is relatively hard to the touch, it is possible that the uterus is clinically sensitive and contracted, which makes it hard to the touch, and the pregnant woman may also feel tightness in the lower abdomen. In this case, it is recommended to go to the hospital for examination in time, and if there is contraction of the uterus, the contraction of the smooth muscle of the uterus should be suppressed to avoid the abruption between the gestational sac and the uterine wall, which may lead to miscarriage. In addition, in clinical cases where there is a history of trauma, the uterus appears hard to the touch and at the risk of causing pain in the lower abdomen. This condition is overwhelmingly caused by placental abruption and it is recommended to pay enough attention to it. For small hematoma, the clinical treatment can be conservative, but for large hematoma, the clinical treatment should be surgical.