RESUMO
BACKGROUND: Early menarche is associated with increased risks for several diseases such as cardiovascular diseases and breast cancer. This analysis aimed at generating evidence on a historical trend towards younger age at menarche among Lebanese girls. METHODS: A secondary analysis was conducted on data consolidated from three serial cross-sectional national surveys of women in Lebanon (2007, 2009 and 2012). A total of 6150 women were included in order to study the association between date of birth intervals and age at menarche. RESULTS: The mean age at menarche was 13.06 years, with a peak of the distribution at age 12. Women born before 1950 had a significantly higher mean age at menarche (13.21) compared to those born in 1970 and thereafter (12.95). A stratified analysis showed that women living outside the metropolitan Greater Beirut (GB) area were characterized by an older mean age at menarche (13.11) in all date of birth intervals compared to those in GB (12.89). However, age at menarche declined more significantly over the last two decades among women outside GB, compared to those living in GB. CONCLUSIONS: Epidemiological figures emerging from this study confirm that trends in Lebanon are in line with a global pattern of decreasing age at menarche. Urban-rural differences suggest that higher caloric content of diet and consequent early overweight, more evident in urban areas, are likely determinants of younger menarche. Evidence from this study calls for an urgent implementation of comprehensive multisectoral obesity prevention in children in Lebanon.