Level 1: Causes of pregnant women’s belly. Pregnant women’s belly refers to the gradual increase in the abdomen as the fetus grows after pregnancy. There are many reasons for pregnant women to have a big belly, including fetal growth, increased amniotic fluid, maternal fat accumulation, etc. Among them, fetal growth is the main cause of pregnant women\’s belly. Level 2: How to protect your big belly during pregnancy It is very important to protect your big belly during pregnancy. First of all, pay attention to your diet and avoid overeating or drinking irritating drinks. Secondly, pay attention to rest and avoid overexertion and standing for long periods of time. also