The outcome of triplet versus twin pregnancies

Objective: The purpose of this study was to examine and to determine whether triplet pregnancies are associated with a significantly greater risk of adverse outcome than are twin pregnancies.

Methods: Maternal and perinatal outcomes were evaluated retrospectively in 41 sets of triplets and twin pregnancies that were matched for maternal age, parity, mode of delivery, preterm delivery, mode of conception, and antepartum complications.

Main outcome measures: Perinatal outcome in triplet versus twin gestation.

Results: Triplets had a significantly lower mean average birth weight than in twin gestation (1,596 vs. 2,317 g, p<0.018) and gestational age at delivery (32.9 vs. 35.9 weeks; p< 0.03). Preterm labour occurred significantly more often in triplet than in twin gestation (80.5 vs. 41.5%) as did preterm delivery (87.8 vs. 46.2%). Triplets required a longer hospital stay than did twins (25 vs. 9 days; p<0.04). There were no significant differences between the groups in number of administrations to the Special Care Baby Unit (32.5 vs. 30.5%). Apgar score <7 at 5 min was significantly more in triplet as compared with twin gestation (17 vs. 6%; p<0.0015). Neonatal deaths occurred significantly more in triplets than in twins (26 vs. 8.5%; p< 0.0001). There were no significant differences between the groups in maternal antepartum or neonatal complications such as anaemia, pregnancy-induced hypertension, placental abruption, respiratory distress syndrome or intraventricular haemorrhage. Preterm labour was the only complication that occurred significantly more often in the triplet than in the twin gestation.

Conclusions: We concluded that this information could be useful in counseling patients with respect to the anticipated perinatal outcome of triplet pregnancies.