The Efficacy of A New Crosslinked Hyaluronan Gel in Prevention of Intrauterine Adhesion

The inclusion criteria: * Patients to be female, aged 18-45 years * Without previous dilatation and curettage * Undergoing dilatation and curettage for the current delayed miscarriage * All participants should be with normal liver/rental function and without systemic disease * Agree to use adequate forms of contraception throughout the study * Be in good compliance with the follow-up examination according to the study protocol. The exclusion criteria: * Known/suspected intolerance or hypersensitivity to hyaluronan or its derivatives * Genital tract malformation * Inflammation of genital tract or pelvic cavity, clinical evidence of cancer in genital tract * Suspected genital tuberculosis * Abnormal blood coagulation * Medical histories of peripheral vascular disease, alcohol/drug abuse, and mental illness * Acute or severe infection * Autoimmune diseases.