Frequency of labor dysfunction in nulliparas over the age of thirty.
D000293:Adolescent; D000328:Adult; D000375:Aging; D003120:Colorado; D005260:Female; D006801:Humans; D008423:Maternal Age; D007744:Obstetric Labor Complications / Q000453:epidemiology*; D010298:Parity; D011247:Pregnancy; D018566:Pregnancy, High-Risk; D014590:Uterine Contraction