[Etiological factors and physiological characteristics of infants with low birth weights].
D005260:Female; D005317:Fetal Growth Retardation / Q000150:complications; D006801:Humans; D007230:Infant, Low Birth Weight / Q000502:physiology*; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000209:etiology*; D007236:Infant, Small for Gestational Age / Q000502:physiology; D011247:Pregnancy