Abstract 5749: Birth weight and sex hormones in adolescent girls: Results from the Dietary Intervention Study in Children (DISC)

Abstract

Abstract The purpose of the present study is to explore the association of birth weight and concentrations of sex hormones (serum estrogens, progesterone, androgens and sex hormone blinding globulin (SHBG)) among girls participating in the Hormone Ancillary Study (HAS) of the Dietary Intervention Study in Children (DISC), a randomized controlled clinical trial to evaluate the effect of a reduced fat diet intervention on serum hormones. Serum was collected at 5 points during the study and captured the participants’ before, during, and after puberty. Of the 301 girls in DISC, 263 participated in the HAS and had a reported birth weight. Hormones were measured by radioimunnoassay and SHBG was measured by an immunoradiometric assay. Mixed linear regression models were used to calculate hormone concentrations during follow-up after controlling for potential covariates including DISC intervention assignment. Preliminary results for 203 participants suggest an inverse association of birth weight and concentration of DHEAS throughout the 7 years of follow-up after adjusting for years until/ since menarche and other covariates (P ≤ 0.05). An inverse association between birth weight and pre-menarche concentration of androstenedione was observed (P ≤ 0.05), but the relationship did not maintain statistical significance after adjusting for years until menarche (P ≤ 0.24); suggesting that effect of birth weight on pre-menarche androstenedione concentrations may occur in part via the association of birth weight and age at menarche. Post-menarche concentrations of SHBG were positively associated with birth weight, independent of years since menarche (P ≤ 0.05) and other covariates. Luteal phase estradiol, free estradiol and estrone concentrations were positively associated with birth weight, independent of years since menarche and other covariates (P = 0.04, 0.03, 0.05 respectively). No association was found among the other hormones under investigation or the follicular phase estrogens. In conclusion, these data suggest that pre-menarche androstenedione concentration may be inversely associated with birth weight, but this association is likely mediated by the relationship of birth weight and age at menarche. Conversely, the relationships between birth weight and DHEAS, post-menarche SHBG, and certain luteal phase estrogens appear to be independent of the effect of birth weight on age at menarche. Although untested, it is possible that birth weight, as a proxy for in utero hormone exposure, could potentially influence breast cancer risk via long-term effects on pubertal sex hormones on breast tissue development. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5749.