contracted pelvis

Between 1980 and 1982 there were 542 singleton breech presentation, of which 254 delivered by cesarean section ( 46.86%) Social factor was the first indication and contracted pelvis came the next.

本文回顾分析我院1980～1982年3年中542例单胎臀位的分娩情况，其中剖腹分娩占46.86%，以社会因素为适应证占38.98%，骨盆狭窄次之。

There were no significant differences in the rates of critical contracted pelvis, prolonged latent phase and active phase between cesarean section and vaginal delivery in the occiput posterior position ( P> 0.05).

而剖宫产组和阴道分娩组骨盆临界狭窄、潜伏期及活跃期延长的发生率比较，差异无显著性意义（P>0.05）。

The main factors that cause shoulder dystocia are fetal macrosomia, contracted pelvis and difficult vaginal operation.

巨大儿、骨盆狭窄和困难阴道助产术是其发生的主要因素。