The hardness of the stomach in the afternoon of the fourth month of pregnancy may be due to occasional contractions, uterine enlargement, gastrointestinal discomfort, etc. The stomach of the fourth month of pregnancy may be hardened in the afternoon of the fourth month of pregnancy. 1. Occasional contractions: four months pregnant every afternoon stomach hard tight hard may be the occasional contraction, usually lasts a relatively short period of time, through the rest of the symptoms can be relieved, may be four months pregnant overworked, sexual stimulation, etc., not accompanied by the shortening of the cervical canal, vaginal bleeding, usually do not need special treatment. 2. uterine enlargement: four months pregnant every afternoon stomach hard and hard may be caused by the gradual enlargement of the uterus, the fetus in the uterine cavity volume increases, the enlarged uterus may be the belly taut and tight, the phenomenon of the stomach tight and hard. 3. gastrointestinal discomfort: four months pregnant gastrointestinal discomfort, such as constipation, indigestion, diarrhea, etc., these will affect the gastrointestinal tract peristalsis or symptoms of bloating, will also show the stomach tight and hard. If your stomach is tight and hard in the fourth month of pregnancy, you can observe it for a while without any other abnormalities, and if it is accompanied by other abnormalities, you need to consult a doctor in a timely manner.