Outcomes of multiplets.

Outcomes, both short and long term, differ between singletons and multiplets. Recently, a number of large, well-designed studies have clarified these differences, particularly in light of major changes in perinatal and neonatal care that have influenced changing outcomes. Accordingly, this article will review risks for singletons, twins and higher-order multiples as whole groups and also after correction for gestational age and other potential confounding variables that differ markedly between the groups. In addition, we will focus on the effects of certain factors such as antenatal steroid therapy and gender. Finally, we will detail the specific long-term risks for multiples in terms of growth and neurodevelopmental disabilities.