Twins and other multiple deliveries.
D001724:Birth Weight; D036861:Delivery, Obstetric / Q000379:methods; D005260:Female; D005313:Fetal Death / Q000209:etiology; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D007746:Labor Presentation; D007743:Labor, Obstetric; D007752:Obstetric Labor, Premature / Q000209:etiology; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011273:Pregnancy, Prolonged; D012306:Risk; D013997:Time Factors; D014310:Triplets; D014427:Twins; D014428:Twins, Conjoined