Gynecomastia Associated with a Combination of High IGF-1 and Estradiol In Adolescents

Nelson Vergel

A Longitudinal Study of Growth, Sex Steroids and Insulin-like Growth Factor I in boys with Physiological Gynecomastia

Physiological gynecomastia is common in pubertal boys and appears to be associated with increased levels of insulin like growth factor-1 (IGF-1) and pubertal growth, but not with a shift in the balance between estrogen and testosterone, a new study suggests.

The findings were published online August 19 in the Journal of Clinical Endocrinology and Metabolism by Mikkel G Mieritz, MD, a PhD student working in the department of growth and reproduction, Rigshospitalet, University of Copenhagen, Denmark, and colleagues.

In their discussion, Mieritz and colleagues note that IGF-1 together with estrogen is essential for the growth of breast tissue, and it appears that the effect of growth hormone on breast growth is mediated through IGF-1. "The stimulatory effect of IGF-1 on breast formation was synergized by [estradiol], which was also elevated in boys with gynecomastia in our study. However, serum testosterone was similarly elevated, leaving the estradiol/testosterone ratio unaltered."
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The question that wasn't answered is why did it stay in the boys after puberty and how to prevent it. I know that I will have to have surgery at this point in my life, but if I were to have children and boys run big time in my family how to prevent this from happening in my child.


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Occasionaly during puberty,some boys who grow up fast,have swollen nipples,as a result of prolactinemia.The reaon is due to the hypersecretion of somatropin from adenohypophysis.As well known,anterior pituitary gland releases HGH & prolactin.Therefore,as growth hormone is leaving pituitary gland,some quantity of prolactin follows.This apparently leads to gynecomastia effect.