Vaughn T C, Powell L C
Obstet Gynecol. 1979 Mar;53(3 Suppl):67S-72S.
A pair of conjoined twins (thoracopagus) was delivered abdominally after antepartum diagnosis. Obstetrical planning is more likely to be successful with antepartum diagnosis, which can be done only if the possibility of conjoining is considered with each twin gestation. Once a twin gestation is suspected, ultrasonography should be performed for confirmation. Conjoined twins should be suspected in a gravid mother with multiple gestations and an abnormal fetal attitude. When the images cannot be separated on ultrasonography, amniographic examination, using a double contrast medium of oil-water, should demonstrate dye in the gastrointestinal tract and a union between the twins, as well as establish the presence of a monoamniotic sac. Because of increased fetal morbidity and mortality of vaginal delivery in monoamniotic twins, even if not conjoined, elective cesarean section at term will ensure the best chance for fetal survival.
一对联体双胎（胸部联体）在产前诊断后经腹娩出。产前诊断有助于产科计划的成功实施，而只有在每次双胎妊娠时都考虑到联体的可能性，才能进行产前诊断。一旦怀疑双胎妊娠，应进行超声检查以确诊。多胎妊娠且胎儿姿势异常的孕妇应怀疑有联体双胎。当超声图像无法分开时，使用油水双重造影剂的羊膜造影检查应显示胃肠道内有造影剂以及双胎之间相连，同时确定单羊膜囊的存在。由于单羊膜囊双胎经阴道分娩时胎儿发病率和死亡率增加，即使未联体，足月选择性剖宫产也将确保胎儿存活的最佳机会。
