ArticleInternational journal of cancer2022
Pregnancy duration and ovarian cancer risk: A 50-year nationwide cohort study.
Article in International journal of cancer, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers.
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Who cites it
17 citing papers in PubMed, 23 citations in OpenAlex.
- Global epidemiology of ovarian cancer: patterns, trends, and risk factors.Cancer biology & medicine · 2026Review
- Cancer Incidence in Women After Medically Assisted Reproduction.JAMA network open · 2026Article
- Targeting Autophagy in Ovarian Cancer: The Emerging Role of Ginsenosides.Cancer medicine · 2026Review
- Biopsychosocial Characteristics of Patients with Primary Fallopian Tube Carcinoma: Retrospective Single-Center Descriptive Pilot Study.Journal of clinical medicine · 2026Article
- Association between childbirth history and multiple health outcomes.Archives of medical science : AMS · 2026Article
- Hypertension and ovarian cancer risk: a meta-analysis of observational studies.Archives of medical science : AMS · 2026Review
- Special Issue "Biomarkers and Early Detection Strategies of Ovarian Tumors".International journal of molecular sciences · 2025Article
- Reproductive factors and risk of epithelial ovarian cancer: results from the Asia Cohort Consortium.British journal of cancer · 2025Article
- Breast and Ovarian Cancers' Incidence Trends Among Iraqi Women During 2012-2022 and Their Relationship to Fertility Patterns.Sultan Qaboos University medical journal · 2025Article
- Epidermal growth factor receptor ligands enriched in follicular fluid exosomes promote oncogenesis of fallopian tube epithelial cells.Cancer cell international · 2024Article
- Global epidemiology of epithelial ovarian cancer.Nature reviews. Clinical oncology · 2024Review
- Underpinnings of the Halachic Approach to BRCA Screening and Intervention: Facilitating Provider Counseling for Observant Jewish Populations.Rambam Maimonides medical journal · 2024Review
- Association Between GermlineInternational journal of general medicine · 2024Article
- Proteomic characterization of epithelial ovarian cancer delineates molecular signatures and therapeutic targets in distinct histological subtypes.Nature communications · 2023Article
- Burden of ovarian cancer in China from 1990 to 2030: A systematic analysis and comparison with the global level.Frontiers in public health · 2023Article
- Pregnancy duration and ovarian cancer risk: A 50-year nationwide cohort study.International journal of cancer · 2022Article
- Understanding How Pregnancy Protects Against Ovarian and Endometrial Cancer Development: Fetal Antigens May Be Involved.Endocrinology · 2022Review
Corrections and comments
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Authors and funding
3 authors at 2 institutions in 4 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
A woman's reproductive history is strongly associated with her risk of ovarian cancer. However, it is unclear how pregnancies of different duration impact a woman's ovarian cancer risk, and therefore, what part of a pregnancy explains the protective effect. Using a cohort of all Danish women followed from 1968 to 2018, with prospectively registered information on reproductive history (eg, gestational duration of pregnancies, tubal ligation and resection and hormonal pharmaceutical use), we investigated the effect of pregnancy duration on ovarian cancer risk. We adjusted for potential confounders, such as age at pregnancy and time since pregnancy, using log-linear Poisson regression to isolate the effect of pregnancy duration on ovarian cancer risk. Among 2.5 million Danish women with 4.4 million pregnancies, a pregnancy was associated with a reduction of ovarian cancer risk of 21% (95% CI, 14%-28%), 26% (95% CI, 21%-31%), 12% (95% CI, 7%-17%) and 3% (95% CI, -5% to 11%) compared to one less, for the first, second, third and fourth pregnancy, respectively (P < .001 for heterogeneity), with similar effects of induced abortions, spontaneous abortions and childbirths. Sensitivity analysis of age at pregnancy, time since pregnancy and other potential confounders did not change these findings. The reduced ovarian cancer risk associated with pregnancy is primarily driven by the first three pregnancies, with similar effects of induced abortion, spontaneous abortions and childbirth, suggesting that mainly exposure to early pregnancy factors, and not pregnancy duration, protect against ovarian cancer.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.