Customized growth charts for twin vs singleton pregnancies and their ability to identify small for gestational age-associated risk of adverse perinatal outcome

Use of a singleton standard for twins results in a 3 times higher small for gestational age rate, without detecting additional cases at risk of stillbirth or adverse neonatal outcomes. The results suggest that the use of a twin-specific chart to monitor twin pregnancies is safe in recognizing small for gestational age-associated risk of adverse outcomes and is likely to result in fewer unnecessary investigations, interventions, and maternal anxiety.