Birth weight and breast cancer risk

Abstract

Many, but not all studies of birth weight and subsequent breast cancer risk suggest a positive association, with the most consistent finding being an association in younger or premenopausal women, often with either no or a reduced association among postmenopausal women (Ekbom et al, 1992;Michels et al, 1996;Sanderson et al, 1996;De Stavola et al, 2000;Innes et al, 2000;Andersson et al, 2001;Hilakivi-Clarke et al, 2001;Titus-Ernstoff et al, 2002;Vatten et al, 2002Vatten et al, , 2005Ahlgren et al, 2003;Kaijser et al, 2003;McCormack et al, 2003;Mellemkjaer et al, 2003;dos Santos Silva et al, 2004;Lahmann et al, 2004).We evaluated the association of birth weight and breast cancer risk in the National Cancer Institute's (NCI) Combined Diethylstilbestrol (DES) Cohorts Follow-up Study. The strengths of this resource are the availability of weight from birth records, adult breast cancer risk factor data from three phases of questionnaire follow-up, and a subset of the population receiving very high pharmacologic doses of oestrogen, which could inform some of the speculation about possible hormonal mechanisms. MATERIALS AND METHODSApprovals for the study were obtained from the committees for the review of research involving human subjects at the field centres and the NCI.The NCI DES Combined Cohort Study started in 1992 with the aggregation of prior US cohorts of individuals with medical record documentation of DES exposure and a comparable cohort of unexposed women (Bibbo et al, 1977;Labarthe et al, 1978;Greenberg et al, 1984). Questionnaires were mailed to participants in 1994, 1997, and 2001, and the National Death Index (NDI)-Plus was used to identify women whose whereabouts were unknown. Of the 5847 eligible subjects with birth weight data who were free of breast cancer at the start of follow-up, 97 developed breast cancer and 1245 were lost before the end of follow-up in 2001; the remaining 4505 were followed through the 2001 data collection phase. Incident cases of breast cancer were identified through questionnaire self-reports and searches of the NDI-Plus. Pathology reports or death certificates were obtained for 91% of the reported breast cancer cases eligible for analysis, confirming invasive disease in 88% and in situ disease in an additional 11%. Only primary invasive cases were analysed.Data on birth weight and gestational age were available from obstetrical charts for 80% of the women. For the remaining 20%, these data were ascertained from the mothers at the time of their daughter's original enrollment in the study (the average age of the daughters ¼ 24 years). Information on covariates was obtained from the study questionnaires, obstetrical records or interviews, or from earlier questionnaires from the original cohort studies.Follow-up began on 1 January 1978 (or the date of first enrollment if it occurred later). Person-years accrued until the earliest of the following dates: first breast cancer diagnosis, last known follow-up, death, or return of the 2001 questionnaire. The median number of follow-up ...

Birth Weight as a Risk Factor for Breast Cancer: A Meta-Analysis of 18 Epidemiological Studies

“…Two studies did not provide adequate information for either dichotomous comparisons or trend analysis, 21,30 2 twins studies were excluded because we were concerned with differences between twins and general birth populations, particularly with regard to birth weight, 31,32 and 10 other studies were excluded because their results were included in other detailed publications that provided more comprehensive results or adequate information. 10,16,17,19,20,22,[33][34][35][36] Thus, the present meta-analysis includes 18 unique studies: 11 case-control studies, 9,13,18,23,[37][38][39][40][41][42][43] and 7 cohort studies 11,12,14,15,24,44,45 (Tables 1 and 2).…”

“…The study populations included participants from the United States, 9,11,[39][40][41]43,44 Europe, 12,15,23,24,37,38,42,45 and China, 18 for a total of 16,424 women with breast cancer. The cases in these studies were primarily obtained from cancer registries, hospital records, or both.…”

Lifecourse predictors of mammographic density: the Newcastle Thousand Families cohort Study

“…Birth-weight has been reported to be positively associated with breast cancer [6][7][8][9][10], particularly among premenopausal women [6,10]. However, the limited research so far into the association between birth weight and mammographic density has reported inconsistent findings [11][12][13][14][15][16].…”

Influence of birth weight and adult body composition on 17β-estradiol levels in young women

“…Interestingly, several studies have observed that perinatal factors, including birth weight, may influence later susceptibility of chronic diseases including breast cancer (25), (26), (5), (27), (28). Moreover, the association related to breast cancer has been complicated by contradictory results (29), (30) because some have observed a protective effect of low birth weight (25), whereas others have not (31). We have previously hypothesized that birth size may influence later responsiveness of ovarian function and have shown that, among adult women ovarian response to physical activity depends on their size at birth (32).…”