In a new study published online on November 25, 2014 in the peer-reviewed scientific journal Environmental Research, scientists showed that in the U.S. adolescent girls with moderate BPA levels were less likely to have early onset of menarche. There is so far only limited epidemiologic data on BPA exposure in children related to pubertal development. McGuinn and colleagues therefore analyzed the National Health and Nutrition Examination Survey (NHANES) 2003–2010 data in order to examine the association of BPA with age at menarche in adolescent girls. The authors hypothesized that urinary BPA levels representing BPA exposure are associated with earlier menarche. Further they assumed that obesity, as measured by body mass index (BMI), might modulate this association. Cross-sectional analyses of urinary BPA, BMI and age of menarche were carried out in a sample of 987 adolescent girls aged 12–19, using pooled data. The results show that adolescent girls with moderate BPA levels appeared to be less likely to have early onset of menarche than those with the lowest BPA levels. BMI was shown to modify the BPA-menarche association. However, the authors stress that the results obtained are based on cross-sectional data collected only once and should be verified in carefully designed longitudinal cohort studies that collect samples on more than one occasion over a period of time.
McGuinn, L.A. et al. (2015). “Urinary bisphenol A and age at menarche among adolescent girls: Evidence from NHANES 2003–2010.” Environmental Research 136, 381–386.