The gut flora is an ecosystem which is composed of various microorganisms in the intestine and has a symbiotic relationship with the human body. These microorganisms participate in various functions such as metabolism，immunity and nutrition in the human intestine，and are closely related to the health of the human body. They are also inextricably linked to the occurrence and development of diseases. The composition of the gut flora of pregnant women has undergone significant changes，and the dysbiosis of the gut flora is also considered important in the occurrence and development of pregnancy-related diseases. Probiotics can improve the intestinal microenvironment and can be used to prevent or treat these pregnancy-related diseases. This article reviews the changes in the gut flora of women with pregnancy - related diseases such as gestational diabetes mellitus，preeclampsia，premature delivery， intrahepatic cholestasis of pregnancy and the effectiveness of probiotics for clinical prevention and treatment. This review is also expected to provide a basis for further research on the mechanism of gut flora affecting the health of pregnant women and higher-quality research on probiotics.