Objective: To analyze the effects of fetal reduction in early pregnancy on obstetric and neonatal outcomes of spontaneously or selectively reduced multiple pregnancies produced by in vitro fertilization-embryo transfer (IVF-ET). Methods: Retrospective study of 6 917 clinical pregnancies from IVF-ET cycles, including 754 multiple pregnancies divided into two groups according to the remaining fetus number: reduced singleton group (n=599) and reduced twin group (n=155); and maternal and neonatal outcomes of two groups were compared to primary singleton group (n=3 589) and primary twin group (n=2 574). Results: The rate of pregnancy complication [9.85%(59/599) versus 6.21%(223/3 589)], preterm birth [19.37%(116/599) versus 10.73%(385/3 589)], low birth weight [9.71%(56/577) versus 4.57% (152/3 324)], perinatal death [0.69%(4/577) versus 0.12%(4/3 324)] and malformation [2.95%(17/577) versus 1.02%(34/3 324)] in reduced singleton group were significantly higher than those in primary singleton group (all P<0.01). There were no significant differences between reduced twin group and primary twin group (all P>0.05). In reduced singleton group, birth defect rate was 2.95%, which was higher than those of the other three groups (P<0.05), in this group spontaneous pregnancy reduction accounted for 89.3% (535/599). Conclusions: (1) The rate of pregnancy complication, preterm birth, low birth weight, perinatal death and malformation in reduced singleton group are still higher than primary singletons, suggesting embryo reduction only is a compensated method in multiple pregnancies. Limiting the number of embryos transferred is the essential solution. (2) The rate of birth defect in spontaneous pregnancy reduction group is higher, so prenatal examination should be reinforced in this group.
目的： 分析体外受精-胚胎移植（IVF-ET）治疗中，多胎妊娠实施早期选择性减胎术或胎儿发生自然减胎后的妊娠并发症和新生儿情况，探讨早期减胎是否能改善多胎妊娠的结局。 方法： 回顾性分析2002年1月至2014年10月期间在重庆市妇幼保健院遗传与生殖研究所接受IVF或卵母细胞胞质内单精子注射法（ICSI）的6 917个临床妊娠周期，其中多胎妊娠（包括双胎、三胎）减胎的周期数为754个，根据减胎（包括选择性减胎和自然减胎）后剩余的胎儿数分组：减胎后单胎组（599个周期）、减胎后双胎组（155个周期），分别与同期未减胎的初始单胎组（3 589个周期）、初始双胎组（2 574个周期）的妊娠期并发症发生率、早产率、低出生体质量儿发生率、围产儿死亡率、出生缺陷发生率进行比较。 结果： （1）减胎后单胎组与初始单胎组比较：妊娠期并发症发生率[9.85%（59/599）、6.21%（223/3 589）]、早产率[19.37%（116/599）、10.73%（385/3 589）]、低出生体质量儿发生率[9.71%（56/577）、4.57%（152/3 324）]、围产儿死亡率[0.69%（4/577）、0.12%（4/3 324）]、出生缺陷发生率[2.95%（17/577）、1.02%（34/3 324）]分别比较，差异均有统计学意义（P均<0.01）。（2）减胎后双胎组与初始双胎组比较：妊娠期并发症发生率、早产率、低出生体质量儿发生率、围产儿死亡率及出生缺陷发生率均无显著差异（P均>0.05）。（3）减胎后单胎组中，出生缺陷发生率达2.95%，较其余3组显著增高，差异有统计学意义（P<0.05）。 结论： （1）辅助生殖技术治疗后的多胎妊娠者，即使在孕早期减胎为单胎，其妊娠期并发症发生率、早产率、低出生体质量儿发生率、围产儿死亡率虽有改善，但仍然高于初始单胎妊娠者。（2）发生自然减胎的多胎妊娠患者，其保留胎儿的畸形发生率有增高趋势，应加强产前检查。.
Keywords: Embryo transfer; Fertilization in vitro; Infant, newborn; Pregnancy outcome; Pregnancy reduction, multifetal; Pregnancy trimester, first.