目的 回顾性分析双胎胎儿畸形的分类及各类畸形比例，初步探讨双胎中各类畸形的相关因素。方法 对双胎合并胎儿畸形的病例，按畸形累及系统、畸形胎儿个数、畸形严重程度及孕妇年龄分组，分析各组畸形的比例，并分析各类畸形与绒毛膜性质、受孕方式及妊娠年龄的关系。结果 267例双胎合并畸形的胎儿中，按畸形的系统分组，比例依次为：心血管畸形 (27.3%)、神经系统畸形(20.6%)、骨骼肢体畸形(15.7%)、泌尿系统畸形(13.1%)、水肿胎(12.0%)、颜面体表畸形(11.6%)、前腹壁畸形(8.2%)、消化系统畸形(6.0%)及呼吸系统畸形(5.6%)。非致死性畸形155例、致死性畸形112例，双胎之一畸形225例（84.3％）、两胎畸形42例（15.7），双胎非特有畸形244例（91.4％）、双胎特有畸形23例（8.6％）。Logistic多因素分析显示：与单绒毛膜双胎畸形相比，双绒毛膜双胎畸形中泌尿系统畸形比例显著增加（P=0.007）；与自然受孕的双胎畸形相比，辅助生育后的双胎畸形中无脑儿比例显著增加(P =0.006）。结论 双胎畸形中心血管畸形比例最大，其次为神经系统畸形，骨骼肢体畸形位于第三；双胎之一畸形比两胎畸形常见；单发畸形比多发畸形常见；双胎非特有畸形比双胎特有畸形常见。
Objective To investigate the classifications, the ratios and related factors of malformations in the fetuses of twin pregnancy. Method 267 twin pregnancies complicated with fetal malformations were analyzed by the ratios of malformations in different groups according to the affected systems, the numbers of affected fetuses, the severity of the malformations, chorionicity, conceived methods and maternal age. Among them, the chorionicity, conceived methods and advanced maternal age were investigated as the related factors of twin malformations. Results The ratios of malformations were as follow: cardiovascular system 27.3%, nervous system 20.6%, musculoskeletal system 15.7%, urinary system 13.1%, hydrops 12.0%, facial system 11.6%, anterior abdominal wall 8.2%, digestive system 6.0%, respiratory system 5.6%. Non-lethal malformations accounted for 58.1%, lethal malformation accounted for 41.9%; one fetus affected was 84.3%, both fetuses affected was 15.7%. There were 91.4% non twin-specific malformations and 8.6% twin-specific malformations. The Logistic multiple factors analysis showed that the dichorionic twins had significant contribution to the increase of urinary malformations` ratio（P =0.007）; The assisted reproductive technology had significant contribution to the increased ratio of the anencephalus`（P =0.006）. Conclusions The cardiovascular system malformation is the most common malformation in twin fetuses, the nervous system malformation is the second and the musculoskeletal system malformation ranks the third；One fetus affected is more common than both fetuses affected；Single defect is more common than multiple defects. Non twin-specific malformations are more than twin-specific malformations.
