American Journal of Obstetrics and Gynecology
ResearchGeneral gynecologyOral contraceptive effectiveness according to body mass index, weight, age, and other factors
Section snippets
Study design
EURAS-OC was a large-scale, prospective, active cohort surveillance study conducted between 2000 and 2005 that characterized and compared the short- and long-term risks of both drospirenone-containing and other progestin-containing OCs in a large cohort of OC users in Europe. The main clinical outcome of interest in EURAS-OC was the occurrence of cardiovascular events (ie, the occurrence of venous thromboembolism, myocardial infarction, stroke, arrhythmia, and sudden death). Secondary a
Results
A total of 59,510 women were enrolled in EURAS-OC. Of these, 836 women were excluded because of protocol violations (failure to sign an informed consent form, enrolled ≥2 times by ≥1 study center, continued use of an existing OC, or failure to initiate treatment). Overall, 58,674 women were observed for 142,475 WYs. The maximum individual duration of follow-up evaluation was up to 5 years (mean, 2.4 years). Overall, 1401 women (2.4%) were lost to follow-up during the study (Figure 1).
The
Comment
The results of the current analysis, which was conducted in a large cohort of women from several European countries and based on a total OC exposure of 112,659 WYs, showed that OCs are associated with high contraceptive effectiveness during routine use in women in Europe. Both increasing age (for age groups of >24 years) and increasing duration of use were associated with lower contraceptive failure rates. Although BMI and absolute weight had little, if any, influence on the contraceptive
Acknowledgments
We thank Lyndal McMillan and Danielle Turner from Wolters Kluwer Health for writing assistance during the preparation of this article.
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Cited by (60)
An overview of contraception in women with obesity
2023, Best Practice and Research: Clinical Obstetrics and GynaecologyNo. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception
2017, Journal of Obstetrics and Gynaecology CanadaCitation Excerpt :Data from the U.S. arm of another similar study of COC users calculated an overall PI of 2.2 (95% CI 2.1 to 2.3), and the life-table estimates of contraceptive failure ranged from 3.0% (95% CI 2.8 to 3.2) after the first year of use to 6.2% (95% CI 5.8 to 6.2) after the third year of use.17 In these studies, 42% to 46% of COC failures were associated with irregular COC intake and 9.5% to 18.3% with vomiting and/or diarrhea.17,18 Poor compliance limits COC effectiveness.19
Gynecologic and Obstetric Consequences of Obesity in Adolescent Girls
2017, Journal of Pediatric and Adolescent GynecologyCombined hormonal contraceptive (CHC) use among obese women and contraceptive effectiveness: a systematic review
2017, ContraceptionCitation Excerpt :EURAS-OC also presented results for contraceptive failure according to obesity status for individual COC formulations containing desogestrel (DSG), dienogest (DNG), drospirenone (DRSP), levonorgestrel (LNG) and CMA. Only obese (BMI≥30 kg/m2) users of CMA experienced statistically significant differences in contraceptive failure compared with women of lower BMI (p=.03) [15]. In a US population, INAS-OC noted that women with a BMI≥35 kg/m2 were at increased risk for contraceptive failure compared to women with a BMI<35 kg/m2 [hazard ratio (HR) 1.5, 95% CI: 1.3–1.8], when controlling for age, parity and educational level but did not report results separately for each COC formulation by progestogen [14].
No. 329-Canadian Contraception Consensus (Part 4 of 4): Chapter 9 - Combined hormonal contraception
2017, Journal of Obstetrics and Gynaecology Canada
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.