The abdomen does not change much in the second month of pregnancy, because the fetus is relatively small in the second month of pregnancy, the size of the fetus at this time is as big as a grape, which will not cause the abdomen to become larger, so do not worry too much. However, when the abdomen increases in the second trimester, it is considered that the obesity is caused by the pregnant woman eating too much. During pregnancy, it is necessary to eat less and more, and it is recommended to eat a varied diet and not to overeat, so as not to cause excessive body fat. In the second trimester, there will be breast swelling and pain, and in some cases, pain in the abdomen. The increase of estrogen and progesterone in the body during the second trimester can easily stimulate the gastrointestinal tract and lead to abdominal pain, and the enlargement of the uterus during the second trimester can cause pain in the surrounding tissues and organs. During pregnancy, you need to have regular ultrasound examinations, as long as the size of the developing baby is in line with the month. You should pay attention to the food you eat to promote the development of the fetus.