Miscarriage is prone to infertility for the following reasons: 1. it is easy to cause inflammatory infection and tubal obstruction; 2. it damages the endometrium, causing adhesions in the uterine cavity and inflammation, resulting in infertility; 3. it is easy to combine pelvic inflammatory disease and infection of the fallopian tubes and ovaries, resulting in infertility; 4. after the endometrium is damaged, the adhesions need to be separated and repaired by hysteroscopy, or when the fallopian tubes are obstructed, treatment such as imaging, tubal cannulation and guidewire intervention should be performed, and the process of repair treatment is also a kind of re-injury.