Results of the search
The flow chart of the study is presented in Figure S1. After rejecting articles not associated with the research question, 11 articles were included in the search for studies describing pregnancy outcomes after attempting natural conception in recurrent miscarriage couples from 96 publications, and 2 articles were included in the search for studies reporting on reproductive outcomes after EM or PGD in RPL carriers. Eleven comparative studies (including PS Zheng 2021, our pending published data) compared the first and/or accumulated pregnancy outcomes of carriers to the pregnancy outcomes of noncarriers after attempting natural conception[8-17]. Two comparative studies compared the pregnancy outcomes of carriers after attempting EM or PGD[18, 19]. The population characteristics of the 13 included studies are shown in the Table 1.