@article{51bc7ff95cc04b549729a58af306c0c7,
title = "History of infertility and risk of breast cancer: a prospective cohort study",
abstract = "Purpose: Research on infertility and risk of breast cancer has been conflicting, potentially because many well-established breast cancer risk factors, such as pregnancy history, are strongly correlated with infertility. Methods: We followed participants in the Nurses{\textquoteright} Health Study II from 1989 to 2015 (n = 103,080) for the development of invasive breast cancer and calculated Hazard Ratios (HR) and 95% confidence intervals (CI) using Cox regression. Participants with a self-reported history of infertility (12 months of trying without conception) were compared to gravid women with no history of infertility. We classified breast cancer by menopausal status and investigated mediation by reproductive factors. Results: Over 26 years of follow-up, 26,208 (25.4%) women reported a history of infertility, and 3,201 women were newly diagnosed with invasive breast cancer. We observed no association between infertility history and risk of overall breast cancer (HR: 1.05, 95% CI: 0.97–1.14) or premenopausal breast cancer (RR: 0.93, 95% CI: 0.83–1.03). However, we observed a modest association between history of infertility and risk of postmenopausal breast cancer (HR: 1.13, 95% CI: 1.00–1.28), approximately 50% of which could be attributed to lower total parity and later age at first birth (95% CI: 8.2%–91.0%). Conclusions: Women with a history of infertility were at increased risk of postmenopausal breast cancer. Older age at first birth and lower total parity explained approximately half of the association between infertility and risk of postmenopausal breast cancer.",
keywords = "Age at first birth, Breast cancer, Infertility, Parity",
author = "Farland, {Leslie V.} and Siwen Wang and Rich-Edwards, {Janet W.} and Gaskins, {Audrey J.} and Chavarro, {Jorge E.} and Wang, {Yi Xin} and Tamimi, {Rulla M.} and Missmer, {Stacey A.}",
note = "Funding Information: This work was supported by grants HD096033 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, U01 CA176726, U01 HL145386. Funding Information: We would like to thank participants in the Nurses{\textquoteright} Health Study cohorts and Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital as home of the Nurses' Health Study II. The authors would like to acknowledge the contribution to this study from central cancer registries supported through the Centers for Disease Control and Prevention{\textquoteright}s National Program of Cancer Registries (NPCR) and/or the National Cancer Institute{\textquoteright}s Surveillance, Epidemiology, and End Results (SEER) Program. Central registries may also be supported by state agencies, universities, and cancer centers. Participating central cancer registries include the following: Alabama, Alaska, Arizona, Arkansas, California, Delaware, Colorado, Connecticut, Florida, Georgia, Hawaii, Idaho, Indiana, Iowa, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Mississippi, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Puerto Rico, Rhode Island, Seattle SEER Registry, South Carolina, Tennessee, Texas, Utah, Virginia, West Virginia, Wyoming. Funding Information: We would like to thank participants in the Nurses{\textquoteright} Health Study cohorts and Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital as home of the Nurses' Health Study II. The authors would like to acknowledge the contribution to this study from central cancer registries supported through the Centers for Disease Control and Prevention{\textquoteright}s National Program of Cancer Registries (NPCR) and/or the National Cancer Institute{\textquoteright}s Surveillance, Epidemiology, and End Results (SEER) Program. Central registries may also be supported by state agencies, universities, and cancer centers. Participating central cancer registries include the following: Alabama, Alaska, Arizona, Arkansas, California, Delaware, Colorado, Connecticut, Florida, Georgia, Hawaii, Idaho, Indiana, Iowa, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Mississippi, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Puerto Rico, Rhode Island, Seattle SEER Registry, South Carolina, Tennessee, Texas, Utah, Virginia, West Virginia, Wyoming. Publisher Copyright: {\textcopyright} 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.",
year = "2023",
month = may,
doi = "10.1007/s10549-023-06907-1",
language = "English (US)",
volume = "199",
pages = "185--193",
journal = "Breast Cancer Research and Treatment",
issn = "0167-6806",
publisher = "Springer New York",
number = "1",
}