Dr. Biro's work focuses on pubertal maturation − how timing of puberty is impacted by the physical, chemical and social environment, and how changes associated with puberty impact adolescent and adult morbidity and mortality.

Dr. Biro is currently working on several grants funded through NIEHS, NCI and NICHD. The major study has followed 379 girls, ages 6 and 7, seen every six weeks at their school or in the Clinical and Translational Research Center (CTRC). The original BCERC generated over 3000 visits. During the visits, girls receive several evaluations: blood pressure, height, weight, skin folds, waist and hip circumference, bioelectrical impedance and pubertal maturation. Blood is drawn every visit, and once a year, urine and blood are obtained for selected biomarkers. Blood is obtained for DNA and RNA (microarray analysis). Parents are called every three months for a 24-hour diet recall. Adherence to the protocol has been very high, with >90 percent retention. Blood has been obtained at over 89 percent of visits, urine over 95 percent of scheduled visits, and study questionnaires at over 97 percent of visits.

Average age at intake into the study was 7.1 years of age. At age 8, 29 percent of white, 48 percent of black and 33 percent of Hispanic girls were breast stage 2 or greater; these proportions are significantly greater than those published by Herman-Giddens et al (1997).

Learn more about the Growing Up Female study.

Learn more about the Breast Cancer and the Environment Research Program.