先天畸形新生儿的染色体核型分析及孕妇再分娩畸形儿的风险研究

Study on the Karyotype and Recurrence Risk of Malformed Newborns

目的研究先天畸形新生儿染色体的核型、高危因素及孕妇再分娩畸形儿的风险。方法１０４例先天畸形儿采用Ｇ显带法进行染色体核型分析。根据核型分正常核型组（５１例）和异常核型组（５３例），分析比较畸形儿与１５３例正常新生儿（对照组）间一系列临床资料的差异。对第１胎分娩畸形儿后再次分娩的孕妇２０例统计畸形再发风险。结果（１）１０４例中异常核型５３例，占５０．９６％，分别为２１，三体（４１例，占异常的７７．３６％）；１８，三体（９例，占异常的１６．９８％）；４５，Ｘ、１ｑ＋和５ｐ＋（各１例）。（２）与对照组比，异常核型组孕妇年龄及早产发生率、正常核型组有不良妊娠史的比例显著升高；两组胎儿窘迫、羊水过多或过少发生率及小于胎龄儿比例显著升高，而出生体重显著下降。（３）２０例中再发畸形６例，畸形的再发生率为３０％。结论（１）染色体核型异常是先天畸形的重要病因；（２）先天畸形的高危因素涉及孕妇年龄、不良妊娠史、宫内发育迟缓、羊水过多或过少等；（３）生育过畸形儿的孕妇下胎畸形的再发生率高。

Objective To survey the karyotype and recurrence risk of malformed newborns. Methods Karyotypes of 104 malformed newborns were analyzed using Gbanding. All cases were devided into two groups depending on their karyotypes: Group 1 with normal karyotype (n=51) and group 2 with abnormal (n=53). Clinical data were compared between malformed groups and control. Women who had the second babies after delivering a malformed (n=20) were included in the statistics of recurrence risk. Results (1) Of 104 cases, 53 had abnormal karyotype (50.96%). They were trisomy 21, trisomy 18, 45X, 1q+ and 5p+ (n=41, 9, 1, 1,1, seperately). (2) Within group 2, women's mean delivery age was elder, while premature delivery rate was higher than that of control (P<0.01, 0.05). In group 1, the proportion of women with abnormal pregnancy history increased as compared with control (P<0.05). The rate of fetal distress, poly/oligohydramnios and small for gestational age (SGA) of two malformed groups was higher apparently than that of control. The birth weight of two malformed groups declined obviously. (3) Within 20 second babies being born after their malformed siblings, 6 were malformed too. The total recurrence rate was 30%. Conclusion (1) Abnormal karyotype is an important cause of congenital malformations; (2) The age pregnant women abnormal pregnancy history, IUGR and poly/oligohydramnios all may be the high risk factors of congenital malformations; (3) The recurrence rate of malformations rises after the first malformed newborn's birth.