In the fourth month of pregnancy, there is a feeling of swelling in the anus, and this condition needs to see if it is serious. In the fourth month of pregnancy, the fetus increases in size and the uterus also increases in size, which can press on the rectum and lead to a feeling of swelling. If the feeling of anal swelling is more serious, and there is also a drop, accompanied by pain in the stomach, consider the possibility of preterm abortion. During this period, you should pay attention to bed rest and observation. If you feel that your symptoms are worsening, it is best to go to the hospital for an ultrasound to determine your condition. If you are sure that there are signs of miscarriage, you should promptly take care of the pregnancy. You should try to pay attention not to eat spicy and stimulating food, otherwise it will stimulate the contraction of the uterus.