The placenta.
Grannum
P A
PA
D005260:Female; D005330:Fetofetal Transfusion / Q000175:diagnosis; D006801:Humans; D010920:Placenta / Q000033:anatomy & histology* / Q000473:pathology; D010922:Placenta Diseases / Q000175:diagnosis*; D011247:Pregnancy; D014463:Ultrasonography