Diagnosis of sickling by placental examination. Geographic differences in incidence.
D001741:Black or African American; D000755:Anemia, Sickle Cell / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D005843:Geography; D006801:Humans; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D014481:United States