Placenta Accreta Spectrum

Abstract

(N Engl J Med. 2018;378:1529–1536) Placenta accreta spectrum, also known as morbidly adherent placenta, refers to an abnormal adherence of the placenta trophoblast to the uterine myometrium, which can lead to severe bleeding, multisystem organ failure, disseminated intravascular coagulation, need for admission to an intensive care unit, hysterectomy, and death. It results from the absence of a normal decidua basalis, usually from surgical trauma, and its incidence has increased during the past decades, along with increasing rates of cesarean delivery (increased by a factor of 8 since the 1970s). The potential for bleeding correlates with the degree to which the placenta has invaded the myometrium, the area of abnormal adherence involved, and the presence or absence of invasion into extrauterine tissues, such as the bladder or parametrial tissues. It is an important contributor to maternal mortality and morbidity in the United States.