Journal of Developmental Origins of Health and Disease

Original Articles

Prenatal smoke exposure and mammographic density in mid-life

M. B. Terrya1a2a3 c1, C. A. Schaefera4, J. D. Floma1, Y. Weia2a5, P. Tehranifara1a2, Y. Liaoa1, S. Bukaa6 and K. B. Michelsa7a8a9

a1 Department of Epidemiology, Columbia University Medical Center, Mailman School of Public Health, New York, NY, USA

a2 Herbert Irving Comprehensive Cancer Center, Columbia Medical Center, New York, NY, USA

a3 The Imprints Center for Genetic and Environmental Lifecourse Studies, Columbia University, Mailman School of Public Health, New York, USA

a4 Kaiser Permanente Division of Research, 2000 Broadway, Oakland, CA, USA

a5 Department of Biostatistics, Columbia University Medical Center, Mailman School of Public Health, New York, NY, USA

a6 Department of Epidemiology, Brown University, Providence, RF, USA

a7 Department of Obstetrics, Gynecology and Reproductive Biology, Obstetrics and Gynecology Epidemiology Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA

a8 Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA

a9 Division of Cancer Epidemiology, Comprehensive Cancer Center Freiburg, Freiburg University, Germany


Tobacco smoke has both carcinogenic effects and anti-estrogenic properties and its inconsistent association with breast cancer risk in observational studies may be because of these competing effects across the lifecourse. We conducted a prospective study of prenatal smoke exposure, childhood household smoke exposure, and adult active smoke exposure and mammographic density, a strong intermediate marker of breast cancer risk, in an adult follow-up of existing US birth cohorts. Specifically, we followed up women who were born between 1959 and 1967 and whose mothers participated in either the Collaborative Perinatal Project (Boston and Providence sites) or the Childhood Health and Development Study in California. Of the 1134 women interviewed in adulthood (ranging in age from 39 to 49 years at interview), 79% had a screening mammogram. Cigarette smoking was reported by mothers at the time of their pregnancy; 40% of mothers smoked while pregnant. Women whose mothers smoked during pregnancy had a 3.1% (95% confidence interval (CI) = −6.0%, −0.2%) lower mammographic density than women whose mothers did not smoke during pregnancy. When we further accounted for adult body mass index and adult smoking status, the association remained (β = −2.7, 95% CI = −5.0, −0.3). When we examined patterns of smoking, prenatal smoke exposure without adult smoke exposure was associated with a 5.6% decrease in mammographic density (β = −5.6, 95% CI = −9.6, −1.6). Given the strength of mammographic density as an intermediate marker for breast cancer, the inverse associations between mammographic density and smoking patterns across the lifecourse may help explain the complex association between cigarette smoking and breast cancer risk.

(Online publication November 10 2011)


c1 Address for correspondence: Dr M. B. Terry, Department of Epidemiology, Columbia University, Mailman School of Public Health, 722 West 168th Street, Room 724 A, New York, NY 10032, USA. (Email