Use of fertility drugs and risk of ovarian cancer: Danish population based cohort study
BMJ 2009; 338 doi: https://doi.org/10.1136/bmj.b249 (Published 06 February 2009) Cite this as: BMJ 2009;338:b249
- Allan Jensen, assistant professor of cancer epidemiology1,
- Heidi Sharif, specialist in obstetrics and gynaecology1,
- Kirsten Frederiksen, associate professor of medical statistics1,
- Susanne Krüger Kjær, professor of cancer epidemiology12
- 1Danish Cancer Society, Institute of Cancer Epidemiology, Strandboulevarden 49, DK-2100, Copenhagen, Denmark
- 2The Juliane Marie Center, Copenhagen University Hospital,
- Correspondence to: A Jensen allan{at}cancer.dk
- Accepted 11 November 2008
Abstract
Objective To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women.
Design Population based cohort study.
Setting Danish hospitals and private fertility clinics.
Participants 54 362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. Included in the analysis were 156 women with invasive epithelial ovarian cancer (cases) and 1241 subcohort members identified in the cohort during follow-up in 2006.
Main outcome measure Effect of four groups of fertility drugs (gonadotrophins, clomifene citrate, human chorionic gonadotrophin, and gonadotrophin releasing hormone) on overall risk of ovarian cancer after adjustment for potential confounding factors.
Results Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity.
Conclusion No convincing association was found between use of fertility drugs and risk of ovarian cancer.
Footnotes
We thank Nick Martinussen for help with data management and all participating hospital departments and private fertility clinics for help with the data collection.
Contributors: SKK and HS established the Danish infertility cohort. All authors contributed to the planning and reporting of the work and had final responsibility for writing the manuscript and the decision to submit it for publication. SKK is the guarantor.
Funding: This research was supported by the Danish Cancer Society. The funding sources were not involved in the study design or data collection, analyses, interpretation of the results, the decision to submit the manuscript for publication, or the writing of the manuscript.
Competing interests: None declared.
Ethical approval: This study was approved by the scientific ethics committee of Copenhagen and Frederiksberg municipalities and the Danish Data Protection Agency.
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