Abstract：
The introduction of assisted reproductive technology and the trend of increasing maternal age at conception have contributed to a significant rise in the incidence of multiple pregnancies. Multiple pregnancies bear several inherent risks for both mother and child. These risks increase with plurality and type of chorionicity. Multifetal pregnancy reduction is the selective abortion of ≥1 fetuses to improve the outcome of the remaining fetus(es) by decreasing the risk of premature birth and other complications.
This study aimed to compare birth outcomes of trichorionic triplets reduced to twins with those of trichorionic triplets and primary dichorionic twins. The added value of this study is the comparison with an additional control group, namely primary dichorionic twins.
This was a retrospective cohort study. Data from January 1990 to November 2016 were collected from the East Flanders Prospective Twin Survey, one of the largest European multiple birth registries. A total of 85 trichorionic triplet pregnancies (170 neonates) undergoing multifetal pregnancy reduction to twins were compared with 5093 primary dichorionic twin pregnancies (10,186 neonates) and 104 expectantly managed trichorionic triplet pregnancies (309 neonates). The assessed outcomes were gestational age at delivery, birthweight, and small for gestational age.
Pregnancy reduction from triplets to twins was associated with higher birthweight (+365.44 g; 95% confidence interval, 222.75-508.14 g; P<.0001) and higher gestational age (1.7 weeks; 95% confidence interval, 0.93-2.46; P<.0001) compared with ongoing trichorionic triplets after adjustment for sex, parity, method of conception, birth year, and maternal age. A trend toward lower risk of small for gestational age was observed. Reduced triplets had, on average, lower birthweight (-263.12 g; 95% confidence interval, -371.80 to -154.44 g; P<.0001) and lower gestational age (-1.13 weeks; 95% confidence interval, -1.70 to -0.56; P=.0001) compared with primary twins. No statistically significant difference was observed between primary twins and reduced triplets that reached 32 weeks of gestation.
Multifetal pregnancy reduction from trichorionic triplets to twins significantly improved birth outcomes. This suggests that multifetal pregnancy reduction of trichorionic triplets to twins is medically justifiable. However, the birth outcomes of primary twins before 32 weeks of gestation are still better than those of reduced triplets. The process of multifetal pregnancy reduction includes at least 1 fetal death by definition, and thus prevention of higher-order pregnancies is preferable.
This study aimed to compare birth outcomes of trichorionic triplets reduced to twins with those of trichorionic triplets and primary dichorionic twins. The added value of this study is the comparison with an additional control group, namely primary dichorionic twins.
This was a retrospective cohort study. Data from January 1990 to November 2016 were collected from the East Flanders Prospective Twin Survey, one of the largest European multiple birth registries. A total of 85 trichorionic triplet pregnancies (170 neonates) undergoing multifetal pregnancy reduction to twins were compared with 5093 primary dichorionic twin pregnancies (10,186 neonates) and 104 expectantly managed trichorionic triplet pregnancies (309 neonates). The assessed outcomes were gestational age at delivery, birthweight, and small for gestational age.
Pregnancy reduction from triplets to twins was associated with higher birthweight (+365.44 g; 95% confidence interval, 222.75-508.14 g; P<.0001) and higher gestational age (1.7 weeks; 95% confidence interval, 0.93-2.46; P<.0001) compared with ongoing trichorionic triplets after adjustment for sex, parity, method of conception, birth year, and maternal age. A trend toward lower risk of small for gestational age was observed. Reduced triplets had, on average, lower birthweight (-263.12 g; 95% confidence interval, -371.80 to -154.44 g; P<.0001) and lower gestational age (-1.13 weeks; 95% confidence interval, -1.70 to -0.56; P=.0001) compared with primary twins. No statistically significant difference was observed between primary twins and reduced triplets that reached 32 weeks of gestation.
Multifetal pregnancy reduction from trichorionic triplets to twins significantly improved birth outcomes. This suggests that multifetal pregnancy reduction of trichorionic triplets to twins is medically justifiable. However, the birth outcomes of primary twins before 32 weeks of gestation are still better than those of reduced triplets. The process of multifetal pregnancy reduction includes at least 1 fetal death by definition, and thus prevention of higher-order pregnancies is preferable.
摘要：
背景：辅助生殖技术的引入和孕妇受孕年龄的增长趋势导致多胎妊娠的发生率显着上升。多胎妊娠对母亲和孩子都有一些固有的风险。这些风险随着绒毛膜的多样性和类型而增加。多胎妊娠减少是指选择性流产≥1个胎儿，以通过降低早产和其他并发症的风险来改善其余胎儿的结局。
目的：本研究旨在比较三胞胎减少为双胞胎的出生结局与三胞胎和原发双胎的出生结局。这项研究的附加值是与额外的对照组的比较，即主要的双色子双胞胎。
方法：这是一项回顾性队列研究。1990年1月至2016年11月的数据来自东佛兰德斯前瞻性双胞胎调查，欧洲最大的多胎出生登记处之一。将总共85例三胎三胎妊娠（170例新生儿）与5093例原发性二胎双胎妊娠（10,186例新生儿）和104例预期管理的三胎三胎妊娠（309例新生儿）进行了比较。评估的结果是分娩时的胎龄，出生体重,而且小于胎龄。
结果：从三胞胎到双胞胎的妊娠减少与更高的出生体重相关（+365.44g；95%置信区间，222.75-508.14g；P<.0001）和更高的胎龄（1.7周；95%置信区间，0.93-2.46；P<.0001）与调整性别后的三胞胎相比，奇偶校验，概念的方法，出生年份,和产妇年龄。观察到胎龄小的风险降低的趋势。减少了三胞胎，平均而言,较低的出生体重(-263.12g；95%置信区间，-371.80至-154.44g；P<.0001）和较低的胎龄（-1.13周；95％置信区间，-1.70至-0.56；P=0.0001）与初生双胞胎相比。在初生双胞胎和达到妊娠32周的三胞胎之间没有观察到统计学上的显着差异。
结论：从三胞胎到双胞胎的多胎妊娠减少显著改善了分娩结局。这表明将三胞胎三胞胎减少为双胞胎的多胎妊娠在医学上是合理的。然而,在妊娠32周之前，初生双胞胎的分娩结果仍然优于减少的三胞胎。根据定义，减少多胎妊娠的过程包括至少1例胎儿死亡，因此，预防高阶妊娠是可取的。
目的：本研究旨在比较三胞胎减少为双胞胎的出生结局与三胞胎和原发双胎的出生结局。这项研究的附加值是与额外的对照组的比较，即主要的双色子双胞胎。
方法：这是一项回顾性队列研究。1990年1月至2016年11月的数据来自东佛兰德斯前瞻性双胞胎调查，欧洲最大的多胎出生登记处之一。将总共85例三胎三胎妊娠（170例新生儿）与5093例原发性二胎双胎妊娠（10,186例新生儿）和104例预期管理的三胎三胎妊娠（309例新生儿）进行了比较。评估的结果是分娩时的胎龄，出生体重,而且小于胎龄。
结果：从三胞胎到双胞胎的妊娠减少与更高的出生体重相关（+365.44g；95%置信区间，222.75-508.14g；P<.0001）和更高的胎龄（1.7周；95%置信区间，0.93-2.46；P<.0001）与调整性别后的三胞胎相比，奇偶校验，概念的方法，出生年份,和产妇年龄。观察到胎龄小的风险降低的趋势。减少了三胞胎，平均而言,较低的出生体重(-263.12g；95%置信区间，-371.80至-154.44g；P<.0001）和较低的胎龄（-1.13周；95％置信区间，-1.70至-0.56；P=0.0001）与初生双胞胎相比。在初生双胞胎和达到妊娠32周的三胞胎之间没有观察到统计学上的显着差异。
结论：从三胞胎到双胞胎的多胎妊娠减少显著改善了分娩结局。这表明将三胞胎三胞胎减少为双胞胎的多胎妊娠在医学上是合理的。然而,在妊娠32周之前，初生双胞胎的分娩结果仍然优于减少的三胞胎。根据定义，减少多胎妊娠的过程包括至少1例胎儿死亡，因此，预防高阶妊娠是可取的。
