Xu Wang-Hong, Xiang Yong-Bing, Ruan Zhi-Xian, Zheng Wei, Cheng Jia-Rong, Dai Qi, Gao Yu-Tang, Shu Xiao-Ou
Department of Epidemiology, Shanghai Cancer Institute, Shanghai, Peoples Republic of China.
Int J Cancer. 2004 Feb 10;108(4):613-9. doi: 10.1002/ijc.11598.
The purpose of our study was to evaluate the association of menstrual and reproductive factors with the risk of endometrial cancer. In a population-based case-control study conducted in urban Shanghai, in-person interviews were completed for 833 women aged 30-69 years and an equal number of controls frequency-matched to cases by age. All cases were newly diagnosed with endometrial cancer between January 1, 1997 and December 31, 2001. The unconditional logistic regression model was employed to derive the adjusted odds ratios (ORs) of endometrial cancer and 95% confidence intervals (CIs) in relation to menstrual and reproductive factors. Earlier menarche age, particularly among premenopausal women, and later menopausal age were associated with an elevated risk of endometrial cancer. A clear dose-response relation between endometrial cancer risk and years of menstruation was observed (p for trend < 0.01). Compared to women ever having a pregnancy and women ever having had a live birth, respectively, nulligravity and nulliparity were both associated with a more than one-fold elevated risk of endometrial cancer. Both completed (OR = 3.02, 95% CI 1.10-8.32 for women never having a complete pregnancy) and incomplete pregnancy (OR = 0.69, 95%CI 0.55-0.87) conferred a protective effect against endometrial cancer, and the protective effect appeared to increase with total number of pregnancies (p for trend = 0.01). The effect of pregnancy on endometrial cancer remained unchanged with increasing time since the last pregnancy. Stillbirth and age at first pregnancy was unrelated to endometrial cancer risk. Our study suggests that prolonged menstruation was related to an increased risk of endometrial cancer while pregnancy, including induced abortion, reduced the risk of endometrial cancer.
我们研究的目的是评估月经和生殖因素与子宫内膜癌风险之间的关联。在上海市市区开展的一项基于人群的病例对照研究中，对833名年龄在30 - 69岁的女性进行了面对面访谈，并选取了同等数量、年龄与病例频数匹配的对照。所有病例均为1997年1月1日至2001年12月31日期间新诊断的子宫内膜癌患者。采用无条件逻辑回归模型得出与月经和生殖因素相关的子宫内膜癌调整比值比（OR）及95%置信区间（CI）。月经初潮年龄较早，尤其是在绝经前女性中，以及绝经年龄较晚，均与子宫内膜癌风险升高相关。观察到子宫内膜癌风险与月经年限之间存在明显的剂量反应关系（趋势p值<0.01）。与曾经怀孕和曾经生育过的女性相比，未孕和未育均与子宫内膜癌风险升高一倍以上相关。足月妊娠（从未有过足月妊娠的女性，OR = 3.02，95%CI 1.10 - 8.32）和未足月妊娠（OR = 0.69，95%CI 0.55 - 0.87）均对子宫内膜癌有保护作用，且这种保护作用似乎随着妊娠总数的增加而增强（趋势p值 = 0.01）。妊娠对子宫内膜癌的影响不会因距上次妊娠时间的增加而改变。死产和首次妊娠年龄与子宫内膜癌风险无关。我们的研究表明，月经时间延长与子宫内膜癌风险增加有关，而妊娠，包括人工流产，可降低子宫内膜癌风险。
