Abstract: Objective:To explore the relationship between chromosomal polymorphism and adverse pregnancy.Methods:Blood lymphocyte isolated from 1 086 patients which had the history of adverse pregnancy were cultured,G banding was stained and the chromosome karyotype was analyzed.Results:One hundred and ninety-eight cases of abnormal karyotype were detected,accounting for 18.23% in all subjects.There were 59 cases of chromosomal polymorphism,accounting for 19.8% in chromosome abnormalities.Among them,there were 27 cases of secondary constriction increased,9 cases of inversion of chromosome 9,7 cases of D/G set with body variant and 16 cases of Y chromosome variation.Conclusions:There is significant relationship between chromosomal polymorphism and adverse pregnancy.The clinical effects can not be ignored.