Are neonatal outcomes of triplet pregnancies different from those of singletons according to gestational age?

Multiple pregnancies sustain the high pace of extreme prematurity. Little evidence is available about triplet gestation given the evolution in their management during the last decades. The aim of the study was to compare the neonatal outcomes of triplets with those of matched singletons in a cohort study.

An observational retrospective cohort study of triplets and matched singletons born between 2004 and 2017 matched by gestational age was conducted. Additionally, the investigation performed in regard to data from the overall Greek population of interest. The primary outcome was mortality or severe neonatal morbidity based on pregnancy type.

A total of 237 triplets of 24-36 weeks' gestation and 482 matched singletons were included. No differences in the primary outcome between triplets and singletons were found. Rates of severe neonatal morbidities did not differ significantly between triplets and singletons. A threshold of 1000 gr for birthweight and 28 weeks' gestation for gestational age determined survival on triplets [OR: 0.08 (95% CI: 0.02-0.40, p=0.0020) and OR: 0.13 (95% CI: 0.03-0.57, p=0.0020) for gestational age and birthweight respectively]. In Greece stillbirths in triplets was 8 times higher than that of singletons (OR: 8.5, 95% CI: 6.9-10.5). From 3,375 triplets, 94 were stillborn, whereas in singletons, 4,659 out of 1,388,273. In our center 5 times more triplets than the expected average in Greece were delivered with no significant difference in stillbirths' rates.

No significant differences were identified in mortality or major neonatal morbidities between triplets and matched singletons highlighting the significance of prematurity and birthweight for these outcomes.