Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Hum Reprod. 2011 Oct;26(10):2750-3. doi: 10.1093/humrep/der221. Epub 2011 Jul 22.
Prior studies have documented increased risks to the offspring of IVF singletons that result from a vanished twin pregnancy. We aim to investigate the effect on perinatal outcomes of having an early vanished triplet in IVF twins.
This is a retrospective cohort study of twins from a large academic IVF practice. Multivariate analysis was performed to examine the perinatal risks--including small for gestational age (SGA), low-birthweight (LBW), preterm delivery and early preterm delivery--in twins that resulted from an early vanished triplet compared with twins without a vanished embryo.
Of 829 IVF twin deliveries, 59 were a result of vanished triplet pregnancies (7.1%). There was no significant increase in SGA, LBW or delivery <37 weeks in the vanished triplets compared with other twins; however, the risk of early preterm birth (<32 weeks) was significantly higher (OR 3.09, 95% CI 1.63-5.87) and the length of gestation of these pregnancies was on average 1.5 weeks shorter (P < 0.01). In addition, the unadjusted mean birthweight was lower by nearly 200 g in the vanished triplet pregnancies (P < 0.01).
IVF twin pregnancies with a vanished triplet are at an increased risk for early preterm birth compared with other twin pregnancies. These pregnancies should be recognized at higher risk for early preterm birth and considered for increased obstetrical monitoring. A significant limitation of this study is that the cause for preterm birth was unknown.
先前的研究记录了体外受精（IVF）单胎妊娠中双胞胎消失妊娠所导致的后代风险增加。我们旨在研究 IVF 双胞胎中早期消失的三胞胎对围产儿结局的影响。
这是一项对大型学术性 IVF 实践中双胞胎的回顾性队列研究。采用多变量分析来检查围产期风险——包括胎儿生长受限（SGA）、低出生体重（LBW）、早产和早期早产——在因早期消失的三胞胎而导致的双胞胎中与无胚胎消失的双胞胎相比。
在 829 例 IVF 双胎分娩中，有 59 例是消失的三胞胎妊娠（7.1%）。与其他双胞胎相比，消失的三胞胎中 SGA、LBW 或<37 周分娩的发生率没有显著增加；然而，早期早产（<32 周）的风险显著升高（OR 3.09，95%CI 1.63-5.87），这些妊娠的平均妊娠时间缩短了 1.5 周（P<0.01）。此外，消失的三胞胎妊娠中未调整的平均出生体重低了近 200 克（P<0.01）。
与其他双胞胎妊娠相比，IVF 双胞胎妊娠中消失的三胞胎更易发生早期早产。这些妊娠应被视为早期早产风险较高，并考虑增加产科监测。本研究的一个显著局限性是早产的原因未知。
