The purpose of this study was to assess the use-effectiveness of oral contraceptives (OCs) in Europe according to body mass index (BMI), weight, age, and other factors.
In a planned secondary analysis, we used data from the European Active Surveillance Study on Oral Contraceptives, which was a prospective active cohort surveillance study of 59,510 OC users, to assess the effectiveness of OCs overall and by BMI, weight, age, duration of use, ethinylestradiol dose, regimen type, starting/switching status, and parity. Self-reported unplanned pregnancies during OC use were confirmed by interview.
An analysis of OC effectiveness (112,659 women-years of exposure and 545 unplanned pregnancies) found little variation in effectiveness by BMI/weight. Failure rates decreased after 30 years of age and with an increasing duration of use.
OC users in Europe reported high contraceptive effectiveness with “typical use.” Failure rates decreased with age and duration of use. BMI and weight had little, if any, influence on effectiveness.
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Published online: June 01, 2009
Accepted: March 6, 2009
Received in revised form: January 26, 2009
Received: October 20, 2008
Cite this article as: Dinger JC, Cronin M, Möhner S, et al. Oral contraceptive effectiveness according to body mass index, weight, age, and other factors. Am J Obstet Gynecol 2009;201:263.e1-9.
Financial support was provided by Bayer Schering Pharma AG, Berlin, Germany.
© 2009 Mosby, Inc. Published by Elsevier Inc. All rights reserved.
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- Factors influencing oral contraceptive effectiveness: Dinger et alAmerican Journal of Obstetrics & GynecologyVol. 201Issue 3
- PreviewThe article below summarizes a roundtable discussion of a study published in this issue of the Journal in light of its methodology, relevance to practice, and implications for future research. Article discussed: Dinger JC, Cronin M, Möhner S, et al. Oral contraceptive effectiveness according to body mass index, weight, age, and other factors. Am J Obstet Gynecol 2009;201:263.e1-9. The full discussion appears at www.AJOG.org , pages e1-4.
- Discussion: ‘Factors influencing oral contraceptive effectiveness’ by Dinger et alAmerican Journal of Obstetrics & GynecologyVol. 201Issue 3
- PreviewIn the roundtable that follows, clinicians discuss a study published in this issue of the Journal in light of its methodology, relevance to practice, and implications for future research. Article discussed: Dinger JC, Cronin M, Möhner S, et al. Oral contraceptive effectiveness according to body mass index, weight, age, and other factors. Am J Obstet Gynecol 2009;201:263.e1-9.