Perinatal Characteristics And Outcome Of Preterm Singleton, Twin And Triplet Infants In Nsw And The Act, Australia

Pankaj Garg ¹, Mohamed E. Abdel-Latif ¹, Srinivas Bolisetty ¹, Barbara Bajuk ², Trina Vincent ² and Kei Lui ^1*

¹ Royal Hospital for Women, Australia
² NSW Centre for Perinatal Health Services Research, Australia

^* To whom correspondence should be addressed. E-mail: kei.lui{at}sesiahs.health.nsw.gov.au.

Accepted 29 July 2009

Abstract

Objective: To compare the perinatal characteristics, neonatal morbidity and mortality of preterm singletons, twins and triplets born at 22-31 weeks’ gestation and admitted to Neonatal Intensive Care Units (NICU) in New South Wales (NSW) and Australian Capital Territory (ACT) between 1994 and 2005.

Methods: Perinatal characteristics and neonatal outcome data were obtained from the regional NICUS Data Collection to test for a priori hypothesis. The 10068 very premature infants studied included 7304 (72.5%) singletons, 2444 (24.2%) twins and 320 (3.2%) triplets.

Results: Assisted conception associated with a higher maternal age contributed to higher twins and triplets admissions that twins (OR 6.9, 95% CI 6.1-8.0) and triplets (OR 35.6, 95% CI 27.6-45.8) were significantly more likely a result of assisted conception. Major neonatal morbidities were similar between the three groups of singleton, twins or triplets. While twins of 22-27 weeks’ gestation (adjusted OR 1.39, 95% CI 1.12-1.72) had higher mortality compared to singletons, mortality only diverged below 24 weeks' gestation. Mortality was predicted by decreasing gestational age, male gender and lack of antenatal steroids, whereas assisted conception was protective against mortality (adjusted OR 0.69, 95% CI 0.57-0.86).

Conclusions: Assisted conception contributed to higher very premature NICU admissions of twins and triplets. Preterm twins at the very extreme of viability had higher mortality compared to singletons. The protective effect of assisted conception against mortality requires further research.