Abstract: With the extensive use of assisted reproductive technology (ART), it is more and more important to evaluate routinely the uterine cavity by hysteroscopy before the in vitro fertilization-embryo transfer (IVF-ET) cycle, particularly in those patients with repeated implantation failure (RIF). It has been confirmed that hysteroscopy in examination and treatment can improve the clinical outcomes of IVF-ET. The incidence of intrauterine abnormity is about 10% to 15% , such as polyps, submucous myoma, septum, adhesions and chronic endometritis. Vaginal sonography, hysterosalpingography, and saline infusion sonography can be used to evaluate the uterine cavity, while hysteroscopy examination is the golden standard for the diagnosis of intrauterine pathologies. However, the histological examination is the last standard for the diagnosis of endometritis. Hysteroscopy is also an effective tool for the treatment of intrauterine pathologies. The pregnant rate can be significantly increased in those women underwent hysteroscopic surgery, such as transcervical resection of the endometrial polyps (TCRP), transcervical resection of the myoma (TCRM), transcervical resection of the septum (TCRS), and transcervical resection of the intrauterine adhesions (TCRA). The duration after hysteroscopic surgery, for the IVF-ET treatment, depends on the kind of hysteroscopic surgery, ranged from 1 to 3 months. It is true that hysteroscopy plays an important role in the diagnosis and treatment of infertility. However, it is still under debate whether all of infertile women have a routine hysteroscopy before their IVF-ET treatment.

Key words:  Hysteroscopy, Reproductive techniques, assisted, Fertilization in vitro, Embryo transfer, Uterine diseases