1985年至1994年期间,对55例双羊膜腔双胎妊娠因常规指征于妊娠14～18周进行羊膜腔穿刺作产前诊断。其中有29例在妊娠的14～15周进行。穿刺方法用G_(22)、10～13cm之腰穿针,经腹壁穿刺,55例中48例一次穿刺进入二个羊膜腔成功,5例穿刺2次,2例3次。操作者在超声波引导下仔细分辨出两个羊膜腔之间的隔膜,穿刺针先进入 Between 1985 and 1994, 55 pairs of double amniotic twin pregnancies were routinely diagnosed by amniocentesis during 14-18 weeks of gestation for routine prenatal diagnosis. Twenty-nine of these were performed during 14-15 weeks of gestation. Puncture was performed on the G (22), lumbar puncture of 10-13cm, abdominal puncture of 48 cases, puncture of the two amniocentesis in 48 of 55 cases, puncture of 5 cases 2 times, and 2 cases 3 times. The operator under the guidance of ultrasound carefully distinguish between the two amniotic membrane between the puncture needle into the first