Exposure to varied environmental factors, including nutrition and contamination, is ubiquitous; thus, all studies examining thelarche
must examine nutrition and contamination histories as well as the age of onset and ethnicity.
Such data fall far short of proving that phthalates play a role in thelarche
, observes Shanna H.
In a cross-sectional survey of 1,706 girls 8 through 16 years of age during 1988 through 1994, increased blood lead level was associated with a decreased likelihood for the attainment of either pubarche or menarche but not thelarche (Wu et al.
Polybrominated biphenyls (PBBs) were found to be associated with premature thelarche in girls who were breast-fed by mothers with high serum PBB levels ([greater than or equal to] 7 [micro]g/L) resulting from exposure to milk from cows given contaminated feed (Blanck et al.
In summary, the purported relationship between phthalate exposure and early thelarche
(Colon et al.
Since 1979, pediatric endocrinologists in Puerto Rico have detected an alarming increase in the number of patients with premature thelarche (4,5).
In 1987, the Puerto Rico Department of Health created by law the Premature Thelarche and Early Sexual Development (PTESD) Registry in response to the observed increase in cases (9).
n (%) Overweight 8 21 Obesity 6 16 Hyperlipidemia 8 21 Insulin resistance 2 5 Osteopenia 2 5 Premature thelarche 1 3
Premature thelarche was detected in one female patient.
four cases of premature Many details of the study thelarche
and raised are unavailable (Nikolov oestrodial levels in chil- 1951) Via (National Lib- dren who had received F.
However, preadolescent girls were different in that they had significantly earlier pubarche and thelarche than did adolescent girls with PCOS, and the disorder developed much sooner after thelarche in the younger girls.
Clinicians should look for early pubarche and thelarche in girls predisposed to PCOS, the investigators said (J.