The effect of lead on puberty time in girls and boys: a systematic review

Puberty is the period of developmental changes from childhood to adulthood and the acquisition of fertility. The time of puberty likely affects future risks such as cancer, metabolic syndrome and cardiovascular diseases. Many evidences point to the role of environmental exposure in changing the time of puberty. This review article was performed with aim to investigate the effect of lead on pubertytime in girls and boys based on the studies performed in this field.

In this review article, English and Persian articles related to observational studies which were indexed in databases of Embase, PubMed, Scopus, ISI Web of Science, SID, and Google Scholar during 2000-2018 with different combinations of the keywords of "lead” and "Puberty" were selected from Medical Subject Headings (MESH). From 182 reviewed articles, 12 articled related to the aim were selected based on inclusion and exclusion criteria and quality of reporting articles according to STROBEchecklist. 

12 articles were classified in two domains of lead effects on the puberty of girls and boys. The results of most studies showed that there was a statistically significant association between blood lead levels in girls, especially high levels, with delayed appearance of menarche, development of breast and growth of pubic hair. In boys, there was a statistically significant association between blood lead levels, especially high levels, with a delay in the process of puberty, including increased testicular mass and growth of pubic hair.

Lead can affect the natural process of puberty, and especially is effective in delaying puberty of girls and boys.