I am currently engaged in working on various studies of breast and ovarian cancer prevention and etiology, primarily using data from the Nurses’ Health Study and Nurses’ Health Study II. In particular, I am interested in understanding the influence of genetic and environmental exposures on reproductive hormones in women, as well as how these hormones relate to cancer risk. Prolactin, a hormone involved in breast development and lactation, is one hormone our research group is studying in relation to breast cancer in premenopausal, perimenopausal, and postmenopausal women. We are also examining the role of other sex hormones including estrogens and androgens. For ovarian cancer, we will examine the relationship of androgens and IGFs to risk.

Another interest is understanding sleep patterns and exposures that influence sleep patterns in various populations. One aspect of this research is understanding how certain exposures, such as electromagnetic fields, stress, and employment status, affect sleep patterns in women. I am collaborating with Dr. Anne McTiernan at the Fred Hutchinson Cancer Research Center to explore the effect of physical activity on subjectively and objectively measured sleep patterns in a randomized trial setting. Further, in the Nurses' Health Study, I am examining how sleep patterns are associated with cognitive function both cross-sectionally and prospectively.

I am also interested in epidemiologic methods, particularly in the area of exposure measurement and the use of biomarkers. In my past and present positions, I am involved in overseeing the conduct of biomarker assays for multiple studies.

Tworoger SS, Yasui Y, Vitiello MV, Schwartz RS, Ulrich CM, Aiello EJ, Irwin ML, Bowen D, Potter JD, McTiernan A. Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women. Sleep. 2003;26(7):830-6. [abstract]

Tworoger SS, Chubak J, Aiello EJ, Ulrich CM, Atkinson C, Potter JD, Yasui Y, Stapleton PL, Lampe JW, Farin FM, Stanczyk FZ, McTiernan A. Association of CYP17, CYP19, CYP1B1, and COMT polymorphisms with serum and urinary sex hormone concentrations in postmenopausal women. Cancer Epidemiol Biomarkers Prev. 2004;13(1):94-101. [abstract]

Tworoger SS, Yasui Y, Chang L, Stanczyk FZ, McTiernan A. Specimen allocation in longitudinal biomarker studies: controlling subject-specific effects by design. Cancer Epidemiol Biomarkers Prev. 2004;13(7):1257-60. [abstract]

Tworoger SS, Davis S, Emerson SS, Mirick DK, Lentz MJ, McTiernan A. Effect of a nighttime magnetic field exposure on sleep patterns in young women. Am J Epidemiol. 2004;160(3):224-9. [abstract]

Tworoger SS, Eliassen AH, Rosner B, Sluss P, Hankinson SE. Plasma Prolactin Concentrations and Risk of Postmenopausal Breast Cancer. Cancer Res. 2004;64(18):6814-6819. [abstract]

Tworoger SS, Missmer SA, Barbieri RL, Willett WC, Colditz GA, Hankinson SE. Plasma sex hormone concentrations and subsequent risk of breast cancer among women using postmenopausal hormones. J Natl Cancer Inst. 2005; 97(8):595-602. [abstract]

Tworoger SS, Hecht JL, Giovannucci E, Hankinson SE. Intake of folate and related nutrients in relation to risk of epithelial ovarian cancer Am J Epidemiol 2006;(in press).