Chung T, Neale E, Lau T K, Rogers M
Department of Obstetrics and Gynecology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.
Acta Obstet Gynecol Scand. 1996 Sep;75(8):720-4. doi: 10.3109/00016349609065734.
External cephalic version at term is not always successful. This trial was done to ascertain whether tocolysis has any effect on the success rate.
A randomized, double blind, controlled trial, with continuous paired sequential analysis. Fifty-one consecutive patients with a singleton fetus in a breech presentation between 36 and 38 weeks gestation, external version being attempted on each. Ritodrine infusion or placebo was infused before attempt at external cephalic version.
A university teaching hospital with 8000 confinements annually.
Version was successful in 17 of the 25 patients given tocolysis, but in only eight of the 25 given placebo (p < 0.01). A positive benefit for tocolysis was shown after version had been completed in 10 pairs of patients. However the trial was continued until 25 pairs had been analyzed. The benefit deteriorated during analysis of the last 15 pairs suggesting that the initial benefit may reflect a learning curve for the procedure.
Tocolysis is likely to improve the success rate of external cephalic version in late pregnancy, especially in nulliparous mothers or where doctors are learning the technique.
足月外倒转术并非总能成功。本试验旨在确定宫缩抑制剂对成功率是否有影响。
一项随机、双盲、对照试验，采用连续配对序贯分析。连续纳入51例妊娠36至38周单胎臀位的患者，对每位患者均尝试进行外倒转术。在尝试外倒转术前输注利托君或安慰剂。
一家每年有8000例分娩的大学教学医院。
接受宫缩抑制剂治疗的25例患者中有17例倒转成功，而接受安慰剂治疗的25例患者中仅有8例成功（p<0.01）。在10对患者完成倒转术后显示宫缩抑制剂有积极益处。然而试验继续进行，直至分析了25对患者。在分析最后15对患者时益处有所下降，提示最初的益处可能反映了该操作的学习曲线。
宫缩抑制剂可能会提高晚期妊娠外倒转术的成功率，尤其是在初产妇或医生正在学习该技术的情况下。
