If you have a bloated stomach when you are 40 days pregnant, it is often due to the following reasons: 1. After pregnancy, due to the increase of estrogen thousands of times, the gastrointestinal peristalsis is slowed down, so there will be a bloated situation. 2. It is recommended to eat more easy-to-digest food and take appropriate walks to improve the situation.2. Because the enlarged uterus makes the ligaments painful to pull, so there will be a bloated stomach. With the further progress of pregnancy, this situation will slowly disappear, but this situation will not be accompanied by vaginal bleeding. 3, the occurrence of preeclampsia, for example, due to the lack of progesterone, so that the uterus smooth muscle contraction, so it will lead to the situation of stomach bloating. So if you are pregnant and have a bloated stomach, you must go to the hospital to do the appropriate tests, such as blood tests of blood HCG and progesterone, to understand whether progesterone symptoms of decline, if with the decline, timely treatment.