TY - JOUR
T1 - Childbirth in young Korean women with previously treated breast cancer
T2 - The SMARTSHIP study
AU - Lee, Hak Min
AU - Kim, Bo Wook
AU - Park, Seho
AU - Park, Sungmin
AU - Lee, Jeon Eon
AU - Choi, Young Jin
AU - Kim, Sung Yong
AU - Woo, Sang Uk
AU - Youn, Hyun Jo
AU - Lee, Ilkyun
N1 - Funding Information:
Acknowledgements This work was supported by the Korean Breast Cancer Society and the Study of Multi-disciplinARy Teamwork for breast cancer survivorSHIP (SMARTSHIP). This study enrolled patients from the National Health Information Database (NHIS-2017-4-011), which was provided and is maintained by the National Health Insurance Service (NHIS). The authors would like to thank the National Health Insurance Service for cooperation.
Publisher Copyright:
© 2019, Springer Science+Business Media, LLC, part of Springer Nature.
PY - 2019/7/30
Y1 - 2019/7/30
N2 - Purpose: Alongside the modern trend of delaying childbirth, the high incidence of breast cancer among young women is causing significant pregnancy-related problems in Korea. We estimated the incidence of childbirth for young Korean breast cancer survivors compared with women who did not have breast cancer using a nationally representative dataset. Methods: Using a database from the National Health Insurance Service in South Korea, we analyzed 109,680 women who were between 20 and 40 years old between 2007 and 2013. They were prospectively followed, and childbirth events were recorded until December 31, 2015. We compared childbirth rates and characteristics between the breast cancer survivors and the noncancer controls. Results: Compared to 10,164 childbirths among 91,400 women without breast cancer (incidence rate: 22.3/1000), 855 childbirths occurred among 18,280 breast cancer survivors (incidence rate: 9.4/1000); the adjusted hazard ratio (HR) for childbirth was 0.41 (95% CI 0.38–0.44). Chemotherapy, endocrine therapy, and target therapy were associated with the decreasing childbirths among survivors, with corresponding adjusted HRs of 0.61 (0.53–0.70), 0.44 (0.38–0.51), and 0.62 (0.45–0.86), respectively. Breast cancer survivors had a lower probability of full-term delivery and a higher frequency of preterm labor than controls, with corresponding adjusted ORs of 0.78 (0.68–0.90) and 1.33 (1.06–1.65), respectively. Conclusions: We showed that a history of breast cancer has a negative effect on childbirth among young premenopausal women in Korea. Breast cancer survivors should be aware that they have a higher risk for preterm labor and are less likely to have a full-term delivery than women without a history of breast cancer.
AB - Purpose: Alongside the modern trend of delaying childbirth, the high incidence of breast cancer among young women is causing significant pregnancy-related problems in Korea. We estimated the incidence of childbirth for young Korean breast cancer survivors compared with women who did not have breast cancer using a nationally representative dataset. Methods: Using a database from the National Health Insurance Service in South Korea, we analyzed 109,680 women who were between 20 and 40 years old between 2007 and 2013. They were prospectively followed, and childbirth events were recorded until December 31, 2015. We compared childbirth rates and characteristics between the breast cancer survivors and the noncancer controls. Results: Compared to 10,164 childbirths among 91,400 women without breast cancer (incidence rate: 22.3/1000), 855 childbirths occurred among 18,280 breast cancer survivors (incidence rate: 9.4/1000); the adjusted hazard ratio (HR) for childbirth was 0.41 (95% CI 0.38–0.44). Chemotherapy, endocrine therapy, and target therapy were associated with the decreasing childbirths among survivors, with corresponding adjusted HRs of 0.61 (0.53–0.70), 0.44 (0.38–0.51), and 0.62 (0.45–0.86), respectively. Breast cancer survivors had a lower probability of full-term delivery and a higher frequency of preterm labor than controls, with corresponding adjusted ORs of 0.78 (0.68–0.90) and 1.33 (1.06–1.65), respectively. Conclusions: We showed that a history of breast cancer has a negative effect on childbirth among young premenopausal women in Korea. Breast cancer survivors should be aware that they have a higher risk for preterm labor and are less likely to have a full-term delivery than women without a history of breast cancer.
KW - Breast cancer survivor
KW - Childbirth
KW - Incidence rate
UR - http://www.scopus.com/inward/record.url?scp=85064817365&partnerID=8YFLogxK
U2 - 10.1007/s10549-019-05244-6
DO - 10.1007/s10549-019-05244-6
M3 - Article
C2 - 31020470
AN - SCOPUS:85064817365
VL - 176
SP - 419
EP - 427
JO - Breast Cancer Research and Treatment
JF - Breast Cancer Research and Treatment
SN - 0167-6806
IS - 2
ER -