Anemia is common in pregnancy, ranging from 5.4% in developed countries to more than 80% in developing countries. Anemia in pregnancy has been associated with prematurity, low birth weight, and adverse pregnancy outcomes.
This review uses clinical vignettes to illustrate the clinical presentations, approach to diagnosis, maternal and fetal implications, and treatment for the common etiologies of anemia in pregnancy.
Normal physiological changes in pregnancy result in alterations of hematological parameters particularly in a reduction of hemoglobin (Hb) concentration. Consequently, the Hb used to define anemia in pregnancy is lower than in nonpregnant patients. As there is an increased requirement of iron in pregnancy, it is not unexpected that iron deficiency remains the most common cause of anemia and warrants a preemptive approach to prevent a further reduction in Hb. The syndromes associated with microangiopathic hemolytic anemia may pose a diagnostic challenge, as there are several potential etiologies that may be difficult to differentiate, and microangiopathic hemolytic anemia can be associated with significant maternal and fetal morbidity and mortality. Anemia secondary to sickle cell disease and autoimmune hemolytic anemia merit special attention because there are risks secondary to red blood cell transfusion and risks to withholding transfusion.
Anemia in pregnancy is potentially associated with maternal and fetal adverse outcomes. Providing evidence-based care is essential to achieving the best pregnancy outcomes.
Obstetricians and gynecologists, family physicians.
After completing this activity, the learner should be better able to describe the normal physiological changes in hematological parameters in pregnancy, recognize common and potentially life-threatening diseases manifested as anemia, and develop an approach to anemia in pregnancy.
*Assistant Professor, Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; †Assistant Professor, Department of Medicine, Divisions of Medical Oncology/Hematology and Obstetric Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto; and ‡Associate Professor, Department of Medicine, Obstetric Medicine, §Assistant Professor, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, and ¶Associate Professor, Departments of Medicine and Laboratory Medicine and Pathobiology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
All authors, faculty, and staff in a position to control the content of this CME activity and their spouses/life partners (if any) have disclosed that they have no financial relationships with, or financial interests in, any commercial organizations pertaining to this educational activity.
Correspondence requests to: Dongmei Sun, MD, MSc, FRCPC, Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London Health Sciences Centre, 800 Commissioners Rd E, Room E6-308, London, Ontario, Canada N6A 5W9. E-mail: Dongmei.Sun@lhsc.on.ca.