The intrauterine hazards of twins.
D000013:Congenital Abnormalities; D004200:Diseases in Twins; D005260:Female; D005313:Fetal Death; D005315:Fetal Diseases; D005317:Fetal Growth Retardation; D005330:Fetofetal Transfusion; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy