Maternal mortality rates in the United States have increased consistently over the past 30 years. A driving force in this trend is increasing maternal comorbid medical conditions in the reproductive age population. Providing care for an increasingly complex patient population has made the Intensive Care Unit (ICU) a vital part of the multidisciplinary care team. We sought to describe the critical care needs of a contemporary and diverse obstetric patient population. This was a case series of all maternal admissions to the ICU at a single large academic medical center over a five year period. We assessed indication for ICU transfer and type of critical care required. Critical care was considered required if modalities of care not available on the labor and delivery unit were employed. This included mechanical ventilation, noninvasive ventilation, intravenous vasoactive infusions, and invasive hemodynamic monitoring. Of the 102 ICU transfers between 2014 and 2019, 18% were in the antepartum period, 2% intrapartum, and 80% in the postpartum period. The majority (58%) of patients transferred to the ICU were multiparous at the time of the index pregnancy. The most common indications for transfer were postpartum hemorrhage (PPH), followed by acute respiratory insufficiency, hypertension, and then sepsis (table 1). The majority (71%) of patients transferred required critical care. Of those requiring critical care, the most common requirements were mechanical ventilation (47%) and invasive hemodynamic monitoring (27%), followed by administration of vasoactive medication (23%). Mortality occurred in 2 of the 102 patients (2.0%). Nearly ¾ of patients transferred to the ICU required critical care interventions, in addition to the intensive monitoring available from a higher level of care. The most common reason for ICU transfer is PPH. The majority of patients transferred to the ICU survived to hospital discharge.View Large Image Figure ViewerDownload Hi-res image Download (PPT)