The social and economic factors affecting the incidence of premature birth.  I.  Premature births without complications of pregnancy.
D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D011247:Pregnancy; D047928:Premature Birth
INFANT, PREMATURE