Abstract • Pediatricendocrinologists in Puerto Rico reported a threefold increase in the number of patients with premature thelarche seen between 1978 and 1981. A matched-pairs case-control study was conducted to evaluate associations with potential environmental exposures to substances with estrogenic activity, as well as with familial factors. Analysis was performed on 120 pairs, the case subjects of which were selected from those diagnosed between 1978 and 1982. In subjects 2 years of age or older at the onset of thelarche, no significant associations were found. In subjects with onset before 2 years of age, significant positive associations were found with a maternal history of ovarian cysts, consumption of soy-based formula, and consumption of various meat products. A statistically significant negative association was found with consumption of corn products. These statistical associations are probably not sufficient to explain the reported increase because in over 50% of the case subjects there was no exposure to any of the risk factors for which statistical associations were found. Exposure to other substances with possible estrogenic effect, such as waste products from pharmaceutical factories and pesticides, was also excluded as a possible cause. These findings suggest that better diagnosis and reporting, or conceivably the presence of entirely new, unsuspected factors, could account for the reported increase. (AJDC 1986;140:1263-1267) References 1. Sáenz de Rodriguez CA, Toro-Solá MA, Conde L, et al: Premature thelarche and ovarian cysts probably secondary to estrogen contamination . Bol Asoc Med PR 1982;74:16-19. 2. Pérez-Comas A: Precocious sexual development in Puerto Rico . Lancet 1982;1:1299-1300.Crossref 3. Haddock L, Lebrón G, Martínez R, et al: Premature sexual development in Puerto Rico: Background and current status, in McLachlan JA (ed): Estrogens in the Environment: Influences on Development . New York, Elsevier Science Publishing Co Inc, 1985. 4. Mills JL, Stolley PD, Davies J, et al: Premature thelarche: Natural history and etiologic investigation . AJDC 1981;135:743-745. 5. Hertz R: Personal experiences emphasizing the environmental impact of estrogens , in McLachlan JA (ed): Estrogens in the Environment . New York, Elsevier Science Publishing Co Inc, 1979, pp 347-352. 6. Zaebst DD, Tanaka S, Haring M: Occupational exposure to estrogens: Problems and approaches , in McLachlan JA (ed): Estrogens in the Environment . New York, Elsevier Science Publishing Co Inc, 1979, pp 377-389. 7. Kimball AM, Hamadeh R, Mahmood RAH, et al: Gynaecomastia among children in Bahrain . Lancet 1981;1:671-672.Crossref 8. Fara GM, Del Corvo G, Bernuzzi S, et al: Epidemic of breast enlargement in an Italian school . Lancet 1979;2:295-297.Crossref 9. Hoffman B: The use of hormones in food-producing animals , in Health Aspects of Residues of Anabolics in Meat . Copenhagen, World Health Organization, 1982, pp 16-27. 10. Bongiovanni AM: An epidemic of premature thelarche in Puerto Rico . J Pediatr 1983; 103:245-246.Crossref 11. Sáenz de Rodríguez CA, Bongiovanni AM, Conde de Borrego L: An epidemic of precocious sexual development in Puerto Rican children . J Pediatr 1985;107:393-396.Crossref 12. Pathre SV, Mirocha CJ: Mycotoxins as estrogens , in McLachlan JA (ed): Estrogens in the Environment . New York, Elsevier Science Publishing Co Inc, 1979, pp 265-278. 13. Katzenellenbogen JA, Katzenellenbogen BS, Tattee T, et al: The chemistry of estrogens and antiestrogens: Relationship between structure, receptor binding and biological activity , in McLachlan JA (ed): Estrogens in the Environment . New York, Elsevier Science Publishing Co Inc, 1979, pp 33-51. 14. Clopper CJ, Pearson ES: The use of confidence or fiducial limits illustrated in the case of the binomial . Biometrika 1934;26:404-413.Crossref 15. Schlesselman JJ: Case-Control Studies . New York, Oxford University Press Inc, 1982. 16. Quiñones PF, Alicea-Ortiz J: Agua subterranea en Puerto Rico , Open File Report No. 85-642. Washington, DC, US Geological Survey, 1985.
American Journal of Diseases of Children – American Medical Association
Published: Dec 1, 1986