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Endocrine Care: Claudia Mau Kai, Katharina M. Main, Anders Nyboe Andersen, Anne Loft, Niels E. Skakkebæk, and Anders Juul Reduced Serum Testosterone Levels in Infant Boys Conceived by Intracytoplasmic Sperm Injection J Clin Endocrinol Metab 2007; 92: 2598-2603 [Abstract] [Full text] [PDF]

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Reduced Serum Testosterone Levels in Infant Boys

Zeev Blumenfeld   (24 October 2007)

Reduced Serum Testosterone Levels in Infant Boys 24 October 2007
Zeev Blumenfeld, Associate Professor Technion-Faculty of Medicine, Haifa, Israel Send letter to journal: Re: Reduced Serum Testosterone Levels in Infant Boys bzeev{at}techunix.technion.ac.il Zeev Blumenfeld	I have read with great interest the recent manuscript by Mau Kai et al. (1) and share the authors' concern regarding possible effect of the intracyoplasmic sperm injection (ICSI) procedure on the neonates' health and future fertility. I believe that two points remain unanswered. Because human breast milk contains gonadotropin releasing hormone (GnRH) (2-4), there is a theoretical possibility that suckling babies may express higher testosterone and estrogen concentration due to GnRH absorption (since gastric peptide absorption occurs in the few months of life), higher pituitary LH secretion and higher gonadal steroid production. To consider this possible bias, the authors should compare sex steroids concentrations in human breast milk fed vs. non- breast fed boys. Second, their observed changes in testosterone concentration and LH/testosterone ratio were unassociated with similar differences in FSH or inhibin-B concentrations. In most male infertility patients, with oligospermia and even azoospermia [non-obstructive] decreased inhibin-B and increased FSH concentrations occur without testosterone or LH changes. Mau Kai et al. different observations suggest another, possibly non-testicular effect. Can the authors suggest an explanation? References 1. Mau Kai C, Main KM, Andersen AN, Loft A, Skakkebaek NE, Juul A. 2007. Reduced serum testosterone levels in infant boys conceived by intracytoplasmic sperm injection. J Clin Endocrinol Metab. 92:2598-2603 2. Baram T, Koch Y, Hazum E, Fridkin M. 1997. Gonadotropin-releasing hormone in milk. Science 198:300-302. 3. Amarant T, Fridkin M, Koch Y. 1982. Luteinizing hormone-releasing hormone and thyrotropin-releasing hormone in human and bovine milk. Eur J Biochem. 127:647-650. 4. Levi LN, Ben-Aroya N, Tel-Or S, Palmon A, Burstein Y, Koch Y. 1996. Expression of the gene for the receptor of gonadotropin-releasing hormone in the rat mammary gland. FEBS Lett. 379:186-190.