Abdominal distension and hardness in the third month of pregnancy is generally a normal phenomenon. During pregnancy, the uterus gradually grows larger, causing the surrounding ligaments to relax and become taut, the ligaments around the uterus are stretched, and the enlarged uterus has a certain degree of influence on the surrounding organs, making the pregnant woman feel bloated and even abdominal pain, which is mostly a normal physiological phenomenon and does not require special treatment. However, it is not excluded that the contractions or body hormones cause bloating and constipation. It is necessary to observe whether there is abdominal pain and bleeding at the same time, and if it occurs frequently, it is recommended to go to the hospital for ultrasound examination in time to observe whether the fetus is developing normally, and if it is normal, there is no need to worry too much. In the third month of pregnancy, pregnant women need to go to the hospital for ultrasound, NT examination, blood system screening, such as blood routine, urine routine, coagulation series, liver and kidney function, blood biochemistry, hepatitis B, syphilis, AIDS, etc., to observe the development of the fetus, and if there is any abnormality, under the guidance of the doctor for treatment.