Cryoelectron Microscopy ; methods ; Crystallography, X-Ray ; Image Processing, Computer-Assisted ; methods ; Models, Molecular ; Molecular Conformation

Objective To summarize and evaluate the characteristics of current recurrent spontaneous abortion (RSA) animal models at home and abroad, and to provide reference and guidance for the standardized preparation of RSA models. Methods"Recurrent spontaneous abortion" and "animal model" were used as co-keywords in CNKI, Wanfang, VIP, PubMed and Web of Science databases to search the RSA animal experimental literature, covering the period up to January 20, 2024, and a total of 1 411 articles were collected. The analysis focused on construction methods and essential elements of RSA animal models, the modeling process and result evaluation, as well as the application of these models in pharmacological and pharmacodynamic research. An Excel table was established for systematic analysis and discussion. Results A total of 138 experimental studies were obtained after screening. In constructing RSA animal models, immunological models were the most widely used in Western medicine (96.92%), with the Clark model being the main one (92.31%). In traditional Chinese medicine (TCM) models, 70.00% were kidney deficiency-luteal inhibition-syndrome combination models, 20.00% were kidney deficiency and blood stasis models, and 10.00% were deficiency-heat syndrome models. Most animals were selected at 6-8 weeks (33.86%) and 8 weeks (32.28%) of age. The majority of animals were paired for mating at 18:00 on the day of cage pairing. In 81.03% of literatures, vaginal plugs were checked once the following morning, with 8:00 being the most common time (17.02%). The most commonly used drug administration cycle was 14 days of continuous gavage after pregnancy. Among the tested drugs, Western drugs were mainly protein-based (29.17%), while TCM drugs were mainly TCM decoction (81.11%). The most frequently used methods for detecting indicators included visual observation of embryos (22.54%), western blot (15.96%), PCR (13.58%), ELISA (12.91%), HE staining (10.80%) and immunohistochemistry (9.39%). Conclusion The etiology of RSA is complex, and corresponding animal models should be established based on different etiologies. Clark model is commonly used in the construction of Western medicine model, while the kidney deficiency-luteal inhibition-syndrome combination model is predominant in TCM. RSA animal model is widely used in related research, but systematic evaluation needs to be strengthened.