经会阴三维超声评估妊娠及分娩对女性肛门括约肌复合体的影响

摘要

目的 采用经会阴三维超声成像技术分析妊娠及分娩对肛门括约肌复合体(ASC)的影响.方法 对131名妇女,包括15名未育女性(未育组)、31名中孕期孕妇(中孕组)、31名晚孕期孕妇(晚孕组)、24名剖宫产产妇(剖宫产组)及30名阴道分娩产妇(阴道分娩组,均为初产妇,产后42～60天)的ASC进行三维容积成像.于静息及缩肛状态下,分别在远端平面测量肛门外括约肌(EAS)3、6、9、12点方向厚度,近、中、远3个平面测量肛门内括约肌(IAS)相同4个位置的厚度,于中部平面测量耻骨直肠肌(PRM)4(左侧)、8(右侧)点方向厚度.对不同状态下、不同方位的各肌肉厚度进行统计学分析.结果 静息状态下,剖宫产组近端平面12点及9点方向、中部平面3点及9点方向IAS厚度均较未育组及阴道分娩组厚(P均＜0.05);剖宫产组及经阴道分娩组远端平面4个方位EAS厚度较晚孕组薄(P均＜0.05).缩肛状态下,晚孕组及剖宫产组近端平面12点及9点方向IAS及远端平面12点EAS的厚度较经阴道分娩组厚(P均＜0.05).静息及缩肛状态下,经阴道分娩组左右两侧PRM厚度较晚孕组及剖宫产组薄(P均＜0.05).未育组静息及缩肛状态下、中孕组缩肛状态下、晚孕组静息状态下PRM的厚度均为左侧大于右侧(P均＜0.05).结论 ASC于中孕期、晚孕期、剖宫产、经阴道分娩发生不同程度变化;ASC增厚是女性在妊娠过程中的自身保护机制.%Objective To explore the effects of pregnancy and delivery on the anal sphincter complex (ASC) with 3D-US imaging technique.Methods Transperineal 3D-US images were obtained in 131 women,including 15 nulliparous women (nulliparous group),31 women in middle pregnancy (middle pregnancy group),31 women in late pregnancy (late pregnancy group),24 underwent cesarean section (cesarean section group) and 30 underwent natural childbirth (natural childbirth group).In the resting and anal shrinking state,external anal sphincter (EAS) thickness was measured at 3,6,9 and 12 o'clock positions at distal plane,internal anal sphincter (IAS) thickness was measured at the same four positions at proximal,middle and distal planes,and at the 4 and 8 o'clock positions,the bilateral puborectails muscle (PRM) at middle plane were measured.Results In resting state,at 12 and 9 o'clock positions on the proximal plane,and 3 and 9 o'clock positions on middle plane,the thickness of IAS of cesarean section group was thicker than those in nulliparous group and natural childbirth group (all P＜0.05).On the distal plane,the thickness of EAS at 4 positions of caesarean section group and the natural childbirth group was thinner than those in the late pregnancy group (all P＜0.05).In anal shrinking state,the thickness of IAS at 12 and 9 o'clock positions on the proximal plane,and the thickness of EAS 12 o'clock position on the distal plane,which later pregnancy and cesarean section group were thicker than those in natural children group (all P＜0.05).In resting and anal shrinking state,the thickness of left and right PRM in natural childbirth group were thinner than those in late pregnancy group and cesarean section group (all P＜0.05).In resting and anal shrinking state of nulliparous group,anal shrinking state of middle pregnancy group,and resting state of late pregnancy group,the thickness of left PRM was thicker than those of right PRM (all P＜0.05).Conclusion ASC changes occur in varying degrees in women in middle pregnancy and [ate pregnancy,also in women after cesarean section and natural childbirth.ASC thickening is a protective mechanism for women during pregnancy.