With the rapid development of assisted reproduction technology, the success rate of IVF technology has been increasing in recent years, the average age of assisted conception patients is about 33 years old, and their clinical pregnancy rate in a single cycle has been stable above 55%, and the success rate of young people is even higher, and the clinical pregnancy rate can reach more than 80% after one fresh cycle and two thawing cycles, however, there are still about 10% of patients who cannot achieve pregnancy after multiple embryo transfers. However, about 10% of patients still cannot obtain pregnancy after multiple embryo transfer, which is also a bottleneck to further improve the pregnancy rate. Based on the current research progress at home and abroad and the characteristics of our hospital, we have explored the following effective experience in improving the endometrial tolerance of patients with repeated implantation failure after excluding the factors affecting embryos. 1. Hysteroscopy and hysteroscopic treatment According to statistics, 25%-50% of patients with recurrent implantation failure have uterine cavity abnormalities, and hysteroscopy, as a safe, minimally invasive and easy to master operation, can describe the morphology of the uterine cavity more visually and evaluate the status of the uterine cavity more accurately, and if necessary, specimens can be retained for pathological examination, and has become the gold standard for diagnosing uterine cavity lesions. In patients with a history of IVF-ET failure, hysteroscopy can significantly improve the success rate of reimplantation by treating endometrial polyps, submucosal fibroids, and uterine adhesions that are suggested during the examination. Therefore, hysteroscopy is recommended for patients with repeated implantation failure to evaluate their uterine cavity before re-implantation in order to obtain the desired pregnancy rate. 2. Timing of “implantation window” The endometrial implantation window refers to the time when the endometrium allows embryo implantation, which is usually around day 20-24 of the normal menstrual cycle and lasts for about 24 h. It is crucial to accurately grasp this 24 h for embryo implantation. However, due to individual differences, the implantation window can be early, late or shortened in about 25% of women. Therefore, the inaccuracy of the endometrial implantation window is one of the most important factors of embryo implantation failure. In our specialized hospital, we have conducted a new individualized exploration of such patients, meticulously understanding and controlling the implantation window unique to the individual at all levels before transferring, which has frequently brought good news. 3.Uterine cavity infusion drug treatment For patients with repeated implantation failure, our specialized hospital also often adopts cavity infusion drug treatment to improve endometrial tolerance, which has the effect of improving endometrial resistance to estrogen and vasoactive drugs, endometrium with unexplained basal exudate echogenicity, having a therapeutic effect on chronic inflammation of endometrium, improving endometrial immune status, and promoting endometrial cell proliferation. According to the current statistics of our specialized hospital, this treatment can significantly improve the pregnancy rate of patients with repeated implantation failure. Endometrial scraping is a mechanical treatment that involves scraping the walls of the endometrium with a spatula on the 3rd-10th day of menstruation, as appropriate, and the intrauterine material can be sent for pathological examination. Studies have shown that scraping before embryo transfer significantly increases the rate of embryo implantation, pregnancy success and live births in patients with repeated implantation failure. The mechanism may be that scraping can remove irregularly hyperplastic endometrium, promote blood supply, trigger inflammatory response, etc., thus improving embryo implantation rate. 5. Management of endometrial thinning The change in endometrial thickness can partly reflect the functional status of the endometrium and thus assess the endometrial tolerance. Although the appropriate endometrial thickness is still debated, there is a consensus that thin endometrium affects embryo implantation. When establishing an artificial endometrium in patients with repeated implantation failure, the use of estrogen can improve uterine development and promote endometrial growth according to the thickness of the endometrium and the follicular development, but the prerequisite is to find the primary cause and treat it with a competitive treatment, such as hysteroscopic treatment, elimination of inflammation and treatment of endocrine etiology. 6.Chinese medicine auxiliary treatment At present, our specialized hospital introduces acupuncture, warm ginger moxibustion, mineral salt package, ultrashort wave physiotherapy and other Chinese medicine appropriate technology, comprehensive patient’s physical state to develop a treatment plan, which has significant effect on increasing the pregnancy rate and improving the patient’s quality of life, some patients according to the cause of Chinese medicine intervention. To sum up, our aim is “not to give up on any patient”. Improving the endometrial tolerance is the key to increase the embryo implantation rate. In the case of patients with repeated implantation failure, we should further investigate the causes, develop individualized treatment plans, adjust the patient’s body and mind to the best condition, and do our best to deliver the little angels to each family.