Twin gestations at woman's hospital, St. Lukes hospital center. II.
D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008423:Maternal Age; D011247:Pregnancy; D013997:Time Factors; D014427:Twins