Maternal BMI in Twin Pregnancies and Impact on Neonatal Outcomes in the Level I Unit: A Retrospective Cohort Study.

Objective: With maternal obesity rates and twin pregnancies on the rise, the aim of this study was to assess the impact of pre-pregnancy or first trimester BMI on short-term neonatal morbidities in twins admitted to a level I unit.

Methods: This retrospective single-centre cohort study was conducted on twins born between January 1, 2010 and December 31, 2013 and admitted to the level I unit at Mount Sinai Hospital in Toronto, Ontario. Twin pairs were categorized according to maternal BMI: underweight (<18.