Cited by 712Venous Thromboembolism Diagnosis and ManagementReproductive Health and ContraceptionBlood Coagulation and Thrombosis Mechanisms

Hormonal contraception and risk of venous thromboembolism: national follow-up study

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Lidegaard, O., Lokkegaard, E., Svendsen, A. L., Agger, C.·2009·BMJ

Abstract

OBJECTIVE: To assess the risk of venous thrombosis in current users of different types of hormonal contraception, focusing on regimen, oestrogen dose, type of progestogen, and route of administration. DESIGN: National cohort study. SETTING: Denmark, 1995-2005. PARTICIPANTS: Danish women aged 15-49 with no history of cardiovascular or malignant disease. MAIN OUTCOME MEASURES: Adjusted rate ratios for all first time deep venous thrombosis, portal thrombosis, thrombosis of caval vein, thrombosis of renal vein, unspecified deep vein thrombosis, and pulmonary embolism during the study period. RESULTS: 10.4 million woman years were recorded, 3.3 million woman years in receipt of oral contraceptives. In total, 4213 venous thrombotic events were observed, 2045 in current users of oral contraceptives. The overall absolute risk of venous thrombosis per 10 000 woman years in non-users of oral contraceptives was 3.01 and in current users was 6.29. Compared with non-users of combined oral contraceptives the rate ratio of venous thrombembolism in current users decreased with duration of use (<1 year 4.17, 95% confidence interval 3.73 to 4.66, 1-4 years 2.98, 2.73 to 3.26, and >4 years 2.76, 2.53 to 3.02; P<0.001) and with decreasing dose of oestrogen. Compared with oral contraceptives containing levonorgestrel and with the same dose of oestrogen and length of use, the rate ratio for oral contraceptives with norethisterone was 0.98 (0.71 to 1.37), with norgestimate 1.19 (0.96 to 1.47), with desogestrel 1.82 (1.49 to 2.22), with gestodene 1.86 (1.59 to 2.18), with drospirenone 1.64 (1.27 to 2.10), and with cyproterone 1.88 (1.47 to 2.42). Compared with non-users of oral contraceptives, the rate ratio for venous thromboembolism in users of progestogen only oral contraceptives with levonorgestrel or norethisterone was 0.59 (0.33 to 1.03) or with 75 mug desogestrel was 1.12 (0.36 to 3.49), and for hormone releasing intrauterine devices was 0.90 (0.64 to 1.26). CONCLUSION: The risk of venous thrombosis in current users of combined oral contraceptives decreases with duration of use and decreasing oestrogen dose. For the same dose of oestrogen and the same length of use, oral contraceptives with desogestrel, gestodene, or drospirenone were associated with a significantly higher risk of venous thrombosis than oral contraceptives with levonorgestrel. Progestogen only pills and hormone releasing intrauterine devices were not associated with any increased risk of venous thrombosis.

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Authors
Lidegaard, O., Lokkegaard, E., Svendsen, A. L., & Agger, C.
Affiliations
University of Copenhagen (DK)
Venue
BMJ
Publisher
BMJ
Published
2009-08-13
Volume
339
Issue
aug13 2
Pages
b2890-b2890
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
OpenAlex
W2027062965
Cited by
709
References
29
Citations by year
2026: 19 · 2025: 39 · 2024: 17 · 2023: 27 · 2022: 35 · 2021: 42 · 2020: 33 · 2019: 31 · 2018: 34 · 2017: 46 · 2016: 32 · 2015: 41 · 2014: 61 · 2013: 74 · 2012: 45
FWCI
44.51
Type
journal article
Language
en
Open access
Licence
cc-by-nc
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • Research at the University of Copenhagen (University of Copenhagen) (submittedVersion)
Funders
Rigshospitalet
Topics
  • Health Sciences › Medicine › Internal Medicine › Venous Thromboembolism Diagnosis and Management
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Reproductive Health and Contraception
  • Health Sciences › Medicine › Hematology › Blood Coagulation and Thrombosis Mechanisms
Keywords
hormonal contraception, venous thromboembolism, deep vein thrombosis, pulmonary embolism, oral contraceptives, estrogen dose, progestogens, levonorgestrel, norethisterone, desogestrel, gestodene, drospirenone, cyproterone, route of administration, duration of use, thrombosis risk
MeSH terms
Adolescent, Adult, Contraceptives, Oral, Combined, Contraceptives, Oral, Hormonal, Denmark, Epidemiologic Methods, Female, Humans, Middle Aged, Age Distribution, Venous Thromboembolism, Young Adult

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