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Background Previous studies from this as well as other research groups suggested that non-invasive chromosome screening (NICS) with embryo culture medium can be used to identify chromosomal ploidy and chromosomal abnormalities. We here report a series of clinical cases utilizing the technology. Methods A total of 45 couples underwent in vitro fertilisation during a period between February 2016 and February 2017. Karyotyping revealed normal chromosomes in both partners in 23 couples, and chromosomal rearrangements in at least one partner in 22 couples. Intracytoplasmic sperm injection (ICSI) was used for fertilization. NICS was carried out using embryo culture medium at the blastocyst stage via multiple annealing and looping-based amplification cycles, whole-genome amplification and next-generation sequencing. Results A total of 413 embryos were obtained; 170 blastocysts were subjected to NICS. The screening showed euploidy in 79 embryos, aneuploidy in 52 embryos, and mosaic ploidy for 33 embryos. The rate of euploidy was comparable in couples with normal karyotype (50.7%; 38/75) vs. chromosomal rearrangement (43.2%; 41/95). A total of 52 euploid embryos (50 oocyte retrieval cycles) were transferred in 43 women. Biochemical pregnancy rate was 72.0% (36/50). Clinical pregnancy rate was 58.0% (29/50). The rate of spontaneous miscarriage was 3/29 (none with chromosomal aneuploidy). A total of 27 healthy babies were delivered. Conclusions NICS could identify embryo chromosomal abnormalities in couples either with or without chromosomal rearrangement, with satisfying clinical outcomes. Electronic supplementary material The online version of this article (10.1186/s12967-019-1827-1) contains supplementary material, which is available to authorized users.

Additional file 1: Table S1. Karyotypes of the patients with chromosomal abnormalities in the chromosomal rearrangement group.

Twenty-seven moss specimens collected from the Guangfayong section (Early Miocene, 22.1 Ma) of the Weichang District, North China were investigated in the present study. Based on the morphological and anatomical features of gametophytes, all specimens were found to belong to three species: Leptodictyum riparium, Drepanocladus subtrichophyllus sp. nov., and Amblystegium varium, all of which belong to the family Amblystegiaceae. The microhabitats and living environments of fossil mosses were also investigated based on comparison with living mosses. The results suggest that these mosses grew primarily at the edges of rivers, streams, and lakes and favored being submerged in streams or lakes in the Weichang District in the Early Miocene.