Tummy ache on day 37 of pregnancy requires careful observation. If it is not accompanied by vaginal bleeding, the abdominal pain is relatively mild and not clinically significant. If the abdominal pain is accompanied by diarrhea, it is mostly considered as intestinal inflammation, which is not related to pregnancy. A routine stool examination can be done, and according to the examination results, appropriate treatment measures can be given. If the abdominal pain is accompanied by vaginal bleeding, it is important to be alert to the possibility of a preterm abortion. However, at this time, the fertilized egg has just been laid and if miscarriage occurs, it often appears as a biochemical pregnancy. If the abdominal pain is mild at this time, with a small amount of vaginal bleeding, it is not excluded as a physiological phenomenon. Since some women can have mild abdominal pain and a small amount of bleeding when the fertilized egg is in the womb, they can continue to be observed. If you are not sure, you can also see your doctor for an ultrasound examination.