Evidence for a crossover in breast cancer risk factors.
D000328:Adult; D000368:Aged; D000375:Aging; D001943:Breast Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000401:mortality; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008393:Marriage; D008875:Middle Aged; D011247:Pregnancy; D011252:Pregnancy Complications, Neoplastic; D012306:Risk; D014481:United States