Safety of pregnancy following breast cancer diagnosis: A meta-analysis of 14 studies

Azim, Hatem A.; Santoro, Luigi; Pavlidis, Nicholas; Gelber, Shari; Kroman, Niels; Azim, Hamdy; Peccatori, Fedro A.

doi:10.1016/j.ejca.2010.09.007

« Previous Next »European Journal of Cancer
Volume 47, Issue 1 , Pages 74-83, January 2011

Safety of pregnancy following breast cancer diagnosis: A meta-analysis of 14 studies

Hatem A. Azim Jr.
- Department of Medical Oncology, Jules Bordet Institute, Brussels, Belgium
- Department of Medical Oncology, National Cancer Institute, Cairo University, Cairo, Egypt
Luigi Santoro
- Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy
Nicholas Pavlidis
- Department of Medical Oncology, University of Ioannina, Ioannina, Greece
Shari Gelber
- International Breast Cancer Study Group Statistical Centre, Dana Farber Cancer Institute, Boston, MA, USA
Niels Kroman
- Department of Breast Surgery and Danish Breast Cancer Cooperative Group, Rigshospitalet, Copenhagen, Denmark
Hamdy Azim
- Department of Clinical Oncology, Cairo University Hospital, Cairo, Egypt
Fedro A. Peccatori
- Department of Medicine, Division of Hematology Oncology, European Institute of Oncology, Milan, Italy
- Corresponding author: Address: Department of Medicine, Division of Hematology Oncology, European Institute of Oncology, Via Ripamonti, 435, 20141, Milan, Italy. Tel.: +39 02 5748 9538; fax: +39 02 9437 9241.

Received 22 July 2010; received in revised form 28 August 2010; accepted 2 September 2010. published online 14 October 2010.

Abstract

Background

Due to the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer before completing their families. Therefore, enquiry into the feasibility and safety of pregnancy following breast cancer diagnosis is on the rise. Available evidence suggests that women with a history of breast cancer are frequently advised against future conception for fear that pregnancy could adversely affect their breast cancer outcome. Hence, we conducted a meta-analysis to understand the effect of pregnancy on overall survival of women with a history of breast cancer.

Methods

Two of the authors independently performed a literature search up to September 2009 with no language restrictions. Eligible studies were published retrospective control-matched, population-based and hospital-based studies that have addressed the impact of pregnancy on the overall survival of women with history of breast cancer. Pooling of data was done using the random effect model. Unpublished statistics from three studies were obtained to perform further subgroup and sensitivity analyses. This included examining the effect of pregnancy according to age at diagnosis, healthy mother effect, type of study, nodal status and other parameters.

Results

Fourteen studies were included in this meta-analysis (1244 cases and 18,145 controls). Women who got pregnant following breast cancer diagnosis had a 41% reduced risk of death compared to women who did not get pregnant [PRR: 0.59 (90% confidence interval (CI): 0.50–0.70)]. This difference was seen irrespective of the type of the study and particularly in women with history of node-negative disease. In a subgroup analysis, we compared the outcome of women with history of breast cancer who became pregnant to breast cancer patients who did not get pregnant and were known to be free of relapse. In this analysis, we did not find significant differences in survival between either group [PRR: 0.85; 95% CI: 0.53–1.35].

Conclusions

This study confirms that pregnancy in women with history of breast cancer is safe and does not compromise their overall survival. Hence, breast cancer survivors should not be denied the opportunity of future conception.

Keywords: Pregnancy after breast cancer, Safety, Counselling, Fertility, Healthy mother effect