Beral V
J Epidemiol Community Health. 1985 Dec;39(4):343-6. doi: 10.1136/jech.39.4.343.
Information on whether a woman had ever had any children was recorded for all deaths registered to ever-married women in England and Wales between 1938 and 1960. Analysis of the relation between parity and cause of death for 1.2 million women aged 45-74 years revealed that parous women had lower mortality from breast, ovarian, and endometrial cancer than did nulliparous women but a higher mortality from diabetes mellitus, gallbladder disease, cancer of the uterine cervix, nephritis and nephrosis, hypertension, ischaemic and degenerative heart disease, cerebrovascular disease, and all causes of death. There is a parallel between the long term effects of pregnancy and of oral contraceptives on health.
1938年至1960年间,英格兰和威尔士所有登记为已婚女性的死亡案例中,都记录了该女性是否育有子女的信息。对120万名年龄在45至74岁之间的女性的生育情况与死因之间的关系进行分析后发现,经产妇女患乳腺癌、卵巢癌和子宫内膜癌的死亡率低于未育妇女,但患糖尿病、胆囊疾病、子宫颈癌、肾炎和肾病、高血压、缺血性和退行性心脏病、脑血管疾病以及所有死因的死亡率更高。怀孕和口服避孕药对健康的长期影响存在相似之处。