Neonatal outcome of preterm discordant twins.

OBJECTIVE

To estimate the influence of fetal growth restriction (FGR) on neonatal morbidity and mortality among premature discordant twin neonates.

STUDY

DESIGN

Our medical records (2002-2007) of preterm twins born at 24-37 weeks' gestation were reviewed. Significant discordance was defined as >15% difference in birth weight. Small for gestational age (SGA) was defined as birth weight <10(th) percentile, and appropriate for gestational age (AGA) was between the 10(th) and 90(th) percentile, according to a twin and sex-adjusted gestational age nomogram. The SGA/AGA group comprised of one SGA twin and its AGA pair (30 pairs). Another group of non-SGA discordant twins was also evaluated (n=40 pairs, AGA/AGA). The morbidity and mortality rates were compared between the groups.

RESULTS

Of the selected outcome variables, the only ones in which the incidence was significantly lower for SGA neonates than their AGA pairs were respiratory distress syndrome (5 vs. 11, P=0.014), apnea (1 vs. 9, P=0.004) and the need for respiratory support (5 vs. 14, P=0.002). Anemia, erythropoietin therapy and hyperbilirubinemia were significantly higher in the SGA twin. All selected outcome variables had similar rates within the AGA/AGA pairs.

CONCLUSION

FGR among premature discordant twin pairs is associated with significantly lower rates of respiratory morbidity and higher anemia and erythropoietin therapy rates. Overall morbidity is similar for discordant non-FGR twin pairs.