Section of Epidemiology, Institute of Cancer Research, Sir Richard Doll Building, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK.
Br J Cancer. 2010 Nov 23;103(11):1760-4. doi: 10.1038/sj.bjc.6605978. Epub 2010 Nov 2.
Early menarche increases breast cancer risk but, aside from weight, information on its determinants is limited.
Age at menarche data were collected retrospectively by questionnaire from 81,606 women aged 16-98, resident in the UK and participating in the Breakthrough Generations Study.
Menarche occurred earlier in women who had a low birthweight (P(trend)<0.001), were singletons (P<0.001), had prenatal exposure to pre-eclampsia (P<0.001) or maternal smoking (P=0.01), were not breastfed (P(trend)=0.03), were non-white (P<0.001), were heavy (P(trend)<0.001) or tall (P(trend)<0.001) compared with their peers at age 7 and exercised little as a child (P(trend)<0.001). Menarcheal age increased with number of siblings (P<0.001) independently of birth order, and had an inverse association with birth order after adjustment for sibship size (P<0.001). In a multivariate model, birthweight, ethnicity, weight, height, exercise, sibship size and birth order remained significant, and maternal age at birth became significant (positive association, P<0.001).
Age at menarche was influenced by both pre- and post-natal factors, and these factors may affect breast cancer risk through this route.
初潮提前会增加乳腺癌风险，但除了体重因素外，有关其决定因素的信息有限。
通过问卷调查，回顾性地收集了 81606 名年龄在 16-98 岁的英国居民的数据，这些女性参加了“突破世代研究”。
与同龄人相比，出生体重较低（P(trend)<0.001）、单胎（P<0.001）、产前患有子痫前期（P<0.001）或母亲吸烟（P=0.01）、未进行母乳喂养（P(trend)=0.03）、非白种人（P<0.001）、体重较重（P(trend)<0.001）或身高较高（P(trend)<0.001）的女性初潮时间更早。与 7 岁时的同龄人相比，初潮年龄随着兄弟姐妹数量的增加而增加（P<0.001），且在调整了兄弟姐妹的数量后，与出生顺序呈反比（P<0.001）。在多变量模型中，出生体重、种族、体重、身高、运动、兄弟姐妹数量和出生顺序仍然显著，且母亲的生育年龄也变得显著（呈正相关，P<0.001）。
初潮年龄受产前和产后因素的影响，这些因素可能通过这种途径影响乳腺癌风险。
