Association of size at birth with adolescent hormone levels, body size and age at menarche: relevance for breast cancer risk

Abstract

Birth size has been positively associated with age at menarche and height in adolescence and adulthood, but the relevant biological mechanisms remain unclear. Among 262 Norwegian term-born singleton girls, birth size measures (weight, length, ponderal index, head circumference and subscapular skin-fold thickness) were analysed in relation to adolescent hormone levels (oestradiol, prolactin, dehydroepiandrosterone sulphate, androstenedione and free testosterone index), age at menarche and adolescent (ages 12.7 -15.5 years) and body size (height, weight, body mass index and waist-to-hip ratio) using survival analysis and general linear modelling. The results were adjusted for gestational age at birth, age and menarcheal status at measurement in adolescence and maternal age at menarche. Birth weight, birth length and head circumference were positively associated with adolescent weight and height, and small birth size was associated with earlier age at menarche. Subscapular skin-fold thickness at birth was not associated with adolescent body size, but low fold-thickness was associated with earlier age at menarche. Measures of birth size were inversely related to circulating levels of dehydroepiandrosterone sulphate in adolescence, but there was no clear association with other hormones. These results suggest that physical and sexual development in puberty and adolescence is influenced by prenatal factors, and in combination, these factors may influence health and disease later in life. (Trichopoulos, 1990) has stimulated studies of birth size in relation to risk factors for BC (Okasha et al, 2003). Birth size is an indicator of foetal growth and may reflect intrauterine exposure to oestrogen, the key factor that was originally proposed to explain a possible association between intrauterine factors and adult BC (Trichopoulos, 1990). Studies have shown that relatively large birth size is associated with later age at menarche (Adair, 2001;Sloboda et al, 2007) and taller body height, both in adolescence (Pietiläinen et al, 2001;Romundstad et al, 2003) and in adulthood (Loos et al, 2002). Adult tallness is associated with higher BC risk, and the positive association between birth size and body height suggests that longitudinal growth in childhood and adolescence may be important determinants for subsequent BC (Michels and Willett, 2004). Birth size has also been inversely related to adrenal androgen production during childhood (Ong et al, 2004) and adolescence (Ibanez et al, 1999). Adult levels of both adrenal and gonadal androgens have been associated with BC risk (Kaaks et al, 2005a, b). The fact that small birth size is associated with earlier age at menarche and higher circulating levels of adrenal androgens cannot be easily reconciled with known BC risk factors, as small birth size may be related to reduced risk, and both early age at menarche and androgens are expected to increase risk.We have examined the relation between birth size characteristics and potential BC risk factors (ESHRE Capri Workshop Group, 2004),...

Understanding rural–urban differences in risk factors for breast cancer in an Indian population

“…Similar to previous studies [38], we observed that height was significantly associated with increased risk of breast cancer in urban women. We did not observe this association for rural women, possibly because of low prevalence of taller women in rural areas.…”

Flexibility in reproductive timing in human females: integrating ultimate and proximate explanations

“…To bear children early, a woman needs to cease stature growth and reach menarche early [49]. To do this, a whole suite of hormonal and growth changes are required several years earlier [41,50,51]. Thus, phenotypic specialization needs to be underway by middle childhood if very early childbearing is going to be possible.…”

Parental age at childbirth and age of menarche in the offspring

“…Currently, existing studies have mainly focused on personal and demographic characteristics, such as obesity and social conditions, as the potential factors influencing the timing of menarche (Roberts et al, 1977;Adair, 2001;Adair and Gorden-Larsen, 2001;Freedman et al, 2002Freedman et al, , 2003Hesketh et al, 2002;Castelo-Branco et al, 2006;Ibanez et al, 2006;Opdahl et al, 2008). Only a few studies have examined exposures at the time of organogenesis, even though fetal programming of the timing of menarche is likely (Vatten et al, 2003;Windham et al, 2004;Axmon, 2006).…”