Veisi Pedram, Nikouei Maziar, Cheraghi Mojtaba, Shahgheibi Sholeh, Moradi Yousef
Student Research Committee, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Department of Obstetrics and Gynecology, School of Medicine, Besat Hospital, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Arch Public Health. 2023 Apr 28;81(1):76. doi: 10.1186/s13690-023-01089-0.
It has been assumed that perinatal factors such as multiple pregnancies may affect subsequent breast cancer risk in the mother. Considering the inconsistencies in the results of case-control and cohort studies published in the world, this meta-analysis was conducted in order to determine the exact association between multiple pregnancies (twins or more) and the breast cancer incidence.
This study was performed as a meta-analysis based on PRISMA guidelines by searching the international databases of PubMed (Medline), Scopus, and Web of Science as well as by screening selected articles based on their subject, abstract and full text. The search time was from January 1983 to November 2022. Then the NOS checklist was used to evaluate the quality of the final selected articles. The indicators considered for the meta-analysis included the odds ratio (OR) and the risk ratio (RR) along with the confidence interval reported in the selected primary studies. The desired analyzes were performed with STATA software version 17 to be reported.
In this meta-analysis, 19 studies were finally selected for analysis, which fully met the inclusion criteria. Of these, 11 were case-control studies and 8 were cohort ones. Their sample size was 263,956 women (48,696 with breast cancer and 215,260 healthy) and 1,658,378 (63,328 twin or multiple pregnancies and 1,595,050 singleton pregnancies), respectively. After combining the results of cohort and case-control studies, the effect of multiple pregnancies on the breast cancer incidence was equal to 1.01 (95% CI: 0.89-1.14; I2: 44.88%, P: 0.06) and 0.89 (95% CI: 0.83-0.95; I2: 41.73%, P: 0.07), respectively.
The present meta-analysis results showed, in general, multiple pregnancies were one of the preventive factors of breast cancer.
人们认为，多胎妊娠等围产期因素可能会影响母亲后续患乳腺癌的风险。鉴于全球发表的病例对照研究和队列研究结果存在不一致性，开展了这项荟萃分析，以确定多胎妊娠（双胞胎或更多）与乳腺癌发病率之间的确切关联。
本研究按照PRISMA指南进行荟萃分析，通过检索国际数据库PubMed（Medline）、Scopus和Web of Science，并根据所选文章的主题、摘要和全文进行筛选。检索时间为1983年1月至2022年11月。然后使用NOS检查表评估最终选定文章的质量。荟萃分析考虑的指标包括优势比（OR）和风险比（RR）以及所选原始研究报告的置信区间。使用STATA软件版本17进行所需分析并报告结果。
在这项荟萃分析中，最终选择了19项研究进行分析，这些研究完全符合纳入标准。其中，11项为病例对照研究，8项为队列研究。它们的样本量分别为263,956名女性（48,696名患有乳腺癌，215,260名健康）和1,658,378名（63,328名双胞胎或多胎妊娠，1,595,050名单胎妊娠）。将队列研究和病例对照研究的结果合并后，多胎妊娠对乳腺癌发病率的影响分别为1.01（95%CI：0.89 - 1.14；I²：44.88%，P：0.06）和0.89（95%CI：0.83 - 0.95；I²：41.73%，P：0.07）。
本荟萃分析结果总体显示，多胎妊娠是乳腺癌的预防因素之一。
