(511) Impact of Weight Discordance on Short-term Postnatal and Neurodevelopmental Outcomes in Triplet pregnancies

Objective: Weight discordance (WD) in multifetal pregnancies is a key concern due to its association with selective fetal growth restriction (sFGR). Although much research has focused on twins, studies on triplets are limited. This study evaluates the impact of WD on short-term postnatal and neurodevelopmental outcomes in triplets.

Study Design: We analyzed triplets delivered at Seoul National University Hospital from November 1997 to December 2022. WD was calculated as: ((birthweight of the largest fetus – birthweight of the smallest fetus) × 100) / birthweight of the largest fetus. Short-term outcomes included neonatal death, respiratory distress syndrome, bronchopulmonary dysplasia, persistent pulmonary hypertension, apnea of prematurity, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, necrotizing enterocolitis, and early-onset sepsis. Neurodevelopmental outcomes were assessed up to 60 months using the Korean Ages and Stages Questionnaires and the Bayley Scales of Infant and Toddler Development, 3rd Edition. ROC curves and Generalized Estimating Equations (GEE) were used to analyze the predictive value.

Results: A total of 436 triplets were analyzed. Short-term outcomes were linked to gestational age but not to WD or birthweight order. ROC curve analysis showed an AUC of 0.550 for short-term outcomes, indicating limited predictive value. GEE analysis found adjusted hazard ratios of 1.08 (95% CI 0.74-1.59) for the middle-sized fetus and 1.48 (95% CI 0.99-2.22) for the smallest fetus, suggesting minimal impact of birthweight order. Neurodevelopmental outcomes also showed no significant correlation with WD, with an AUC of 0.645. No differences in outcomes based on WD were seen when analyzed by chorionicity.

Conclusion: This study found no strong association between WD and short- or long-term complications in liveborn triplets. WD does not appear to be a significant predictor of adverse outcomes in triplet pregnancies, though further research is needed for a thorough understanding.