Pregnancy is a time of tremendous physiologic change and vulnerability. At any point, symptoms and complications can prompt the need for emergency care, and these can range from minor to life-threatening. Emergency physicians must be prepared to treat any of these complications, in addition to rescucitating the critically ill and injured pregnant patient. To optimally care for these patients, it is paramount to be aware of the unique physiologic changes that occur during pregnancy. The focus of this review is to discuss illnesses unique to pregnancy and additional aspects of resuscitation that must be considered when caring for a critically ill pregnant patient.