Risk factors for trisomy 21: maternal cigarette smoking and oral contraceptive use in a population-based case-control

Q Yang1, S L Sherman, T J Hassold

  • 1Division of Birth Defects and Developmental Disabilities and the Office of Genetics and Disease Prevention, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA. qay0@cdc.gov

Abstract

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