体外受精-胚胎移植后3胎妊娠有无行减胎术的妊娠结局

Pregnancy reduction of triplets to twins after in vitro fertilization and embryo transfer:a retrospective comparison of pregnancy outcome

目的：比较体外受精-胚胎移植后3胎妊娠行减胎术患者与未行减胎术患者的妊娠结局。方法：回顾性分析2002年1月-2005年12月于我院生殖中心行辅助生育技术后获3胎妊娠的20例患者，按有无行减胎术分组，未减胎组5例，减胎（减为双胎妊娠）组15例。15例减胎术根据胚芽大小采用经阴道B超引导下的微创减胎术，包括抽吸胚芽、抽吸加机械破坏和注射氯化钾3种方法。比较两组的流产率、早产率、分娩时平均孕周、新生儿平均出生体重和〈2500g低出生体重新生儿的比例。结果：两组流产率无差异，减胎组无术后1个月内近期流产病例；未减胎组和减胎组的早产率分别为100％和30．8％，差异显著（P〈0．05），相对危险度为3．25；未减胎组和减胎组分娩时的平均孕周、新生儿平均出生体重分别为（31．8±1．5）周和（36．9±1．6）周、（1720±194）g和（2584±428）g，差异显著（P=0．000）；〈2500g的低出生体重新生儿比例未减胎组比减胎组明显增加（P=0．000）。结论：对体外受精一胚胎移植后3胎妊娠的患者行减胎术减为双胎可以显著改善妊娠结局，早期妊娠胚胎减灭术安全、有效。

Objective： To compare the outcome of triplets obtained after in vitro fertilization and embryo transfer （ IVF - ET） managed expectantly or by selective reduction to twins and to assess the potential benefit of pregnancy reduction. Methods： From 2001 to 2005, a retrospective, comparative and monocentric study about 20 women with triplets after IVF - ET was carried out. 5 cases refused reduction and were expectantly managed while 15 cases chose reduction to obtain twins. According to the size of embryonic bud, pregnancy reduction was conducted with three methods under the guidance of transvaginal ultrasonography, including simple embryonic bud aspiration, combined use of aspiration and mechanically puncture and drug injection directly to the fetus＇heart. Main outcome measures were miscarriage rate, preterm birth rate, gestational age, infants＇birth weight and rate of low birth weight infants （ no more than 2 500 g） . Results： Miscarriage rate was similar, while preterm birth rate had significant difference （ 100% versus 30. 8% ） between expectantly managed group and reduction group （P 〈0. 05 ） . Gestational age and infants＇birth weight in expectantly managed group were significantly lower than that in reduction group （P =0. 000）, （31.8±1. 5） week versus （36. 9 ±1. 6） week and （ 1 720 ± 194） g versus （2 584 ±428） g respectively. Rate of low birth weight infants in expectantly managed group was significantly higher than that in reduction group （P = 0. 000） . Conclusion： Reduction of triplets to twins is effective to improve preterm birth and fetal growth. Ultrasound - guided multiple pregnancy reduction conducted at the early stage of pregnancy is a safe and effective procedure.