Blood grouping in twin pregnancy.
D000650:Amnion; D001769:Blood; D001789:Blood Group Antigens; D005321:Extraembryonic Membranes; D005260:Female; D006801:Humans; D008297:Male; D010920:Placenta; D011247:Pregnancy; D011272:Pregnancy, Multiple; D012732:Sex Determination Analysis; D014427:Twins; D014470:Umbilical Cord
D001789:Blood Group Antigens