Giorgione Veronica, Briffa Corey, Di Fabrizio Carolina, Bhate Rohan, Khalil Asma
Twins Trust Centre for Research and Clinical Excellence, St George's University Hospitals NHS Foundation Trust, Blackshaw Road, London SW17 0RE, UK.
Vascular Biology Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, Cranmer Terrace, London SW17 0RE, UK.
J Clin Med. 2021 Feb 8;10(4):643. doi: 10.3390/jcm10040643.
Twin pregnancies are commonly assessed using singleton growth and birth weight reference charts. This practice has led to a significant number of twins labelled as small for gestational age (SGA), causing unnecessary interventions and increased risk of iatrogenic preterm birth. However, the use of twin-specific charts remains controversial. This study aims to assess whether twin-specific estimated fetal weight (EFW) and birth weight (BW) charts are more predictive of adverse outcomes compared to singleton charts. Centiles of EFW and BW were calculated using previously published singleton and twin charts. Categorical data were compared using Chi-square or McNemar tests. The study included 1740 twin pregnancies, with the following perinatal adverse outcomes recorded: perinatal death, preterm birth <34 weeks, hypertensive disorders of pregnancy (HDP) and admissions to the neonatal unit (NNU). Twin-specific charts identified prenatally and postnatally a smaller proportion of infants as SGA compared to singleton charts. However, twin charts showed a higher percentage of adverse neonatal outcomes in SGA infants than singleton charts. For example, perinatal death (SGA 7.2% vs. appropriate for gestational age (AGA) 2%, < 0.0001), preterm birth <34 weeks (SGA 42.1% vs. AGA 16.4%, < 0.0001), HDP (SGA 21.2% vs. AGA 13.5%, = 0.015) and NNU admissions (SGA 69% vs. AGA 24%, < 0.0001), when compared to singleton charts (perinatal death: SGA 2% vs. AGA 1%, = 0.029), preterm birth <34 weeks: (SGA 20.6% vs. AGA 17.4%, = 0.020), NNU admission: (SGA 34.5% vs. AGA 23.9%, < 0.000). There was no significant association between HDP and SGA using the singleton charts ( = 0.696). In SGA infants, according to the twin charts, the incidence of abnormal umbilical artery Doppler was significantly more common than in SGA using the singleton chart (27.0% vs. 8.1%, < 0.001). In conclusion, singleton charts misclassify a large number of twins as at risk of fetal growth restriction. The evidence suggests that the following twin-specific charts could reduce unnecessary medical interventions prenatally and postnatally.
双胎妊娠通常使用单胎生长和出生体重参考图表进行评估。这种做法导致大量双胞胎被标记为小于胎龄儿（SGA），从而引发不必要的干预措施，并增加医源性早产的风险。然而，使用双胎特异性图表仍存在争议。本研究旨在评估与单胎图表相比，双胎特异性估计胎儿体重（EFW）和出生体重（BW）图表是否能更准确地预测不良结局。使用先前发表的单胎和双胎图表计算EFW和BW的百分位数。分类数据使用卡方检验或McNemar检验进行比较。该研究纳入了1740例双胎妊娠，并记录了以下围产期不良结局：围产期死亡、孕周<34周的早产、妊娠高血压疾病（HDP）以及新生儿重症监护病房（NNU）收治情况。与单胎图表相比，双胎特异性图表在产前和产后识别出的SGA婴儿比例更低。然而，双胎图表显示SGA婴儿的不良新生儿结局百分比高于单胎图表。例如，与单胎图表相比（围产期死亡：SGA 2% vs.适于胎龄儿（AGA）1%，P = 0.029），双胎图表显示围产期死亡（SGA 7.2% vs. AGA 2%，P<0.0001）、孕周<34周的早产（SGA 42.1% vs. AGA 16.4%，P<0.0001）、HDP（SGA 21.2% vs. AGA 13.5%，P = 0.015）以及NNU收治（SGA 69% vs. AGA 24%，P<0.0001）。使用单胎图表时，HDP与SGA之间无显著关联（P = 0.696）。根据双胎图表，在SGA婴儿中，异常脐动脉多普勒的发生率明显高于使用单胎图表的SGA婴儿（27.0% vs. 8.1%，P<0.001）。总之，单胎图表将大量双胞胎错误分类为有胎儿生长受限风险。证据表明，以下双胎特异性图表可减少产前和产后不必要的医疗干预。
