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Active, not recruitingNCT03285230E3NUpdated Jun 25, 2026

The French E3N Prospective Cohort Study

An observational study in Breast Cancer, Colo-rectal Cancer and Parkinson Disease, sponsored by Institut National de la Santé Et de la Recherche Médicale, France. Active, not recruiting at 1 site in France. Open to female participants aged 40 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-25.

Sponsored by Institut National de la Santé Et de la Recherche Médicale, France · Observational

Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
100,000
Ages
40 Years and older
Sex
Female
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Study summary

The French E3N cohort was initiated in 1990 to investigate the risk factors associated with cancer and other major non-communicable diseases in women.

The participants were insured through a national health system that primarily covered teachers, and were enrolled from 1990 after returning baseline self-administered questionnaires and providing informed consent. The cohort comprised nearly 100 000 women with baseline ages ranging from 40 to 65 years.

Follow-up questionnaires were sent approximately every 2-3 years after the baseline and addressed general and lifestyle characteristics together with medical events (cancer, cardiovascular diseases, diabetes, depression, fractures and asthma, among others). The follow-up questionnaire response rate remained stable at approximately 80%.

A biological material bank was generated and included blood samples collected from 25 000 women and saliva samples from an additional 47 000 women.

Ageing among the E3N cohort provided the opportunity to investigate factors related to agerelated diseases and conditions as well as disease survival.

Read the detailed description

Who is in the cohort? In June 1990, a questionnaire was sent to 500 000 women who had been born between 1925 and 1950 and were insured by the Mutuelle Générale de l'Education Nationale (MGEN), a national health insurance plan that primarily covers teachers. The questionnaire was sent along with a leaflet explaining that an Inserm research team was launching a study of cancer risk factors and that participation would require filling in questionnaires every 2-3 years as well as the submission of a signed consent form providing permission to obtain information about each participant's vital status, address changes and medical expense reimbursements from the insurance plan. Nearly 100 000 women volunteered.

How often have they been followed-up? Until now, nine follow-up questionnaires have been sent every 2-3 years from the baseline. Approximately half of the answers were obtained after the first mailing. Two reminders were sent thereafter. The questionnaires were accompanied with newsletters that informed participants about the major results obtained to date. The participation rate remained high (77-92% according to the questionnaires) and the lost to follow-up rate was minimal because of the ability to trace non-respondents through their insurance plan files. The questionnaires were accurately filled in, with few missing or unacceptable answers.

What has been measured? To date, 11 self-administered questionnaires have been sent. The collected data are sociodemographic factors, anthropometric measurements, reproductive factors, hormonal treatments, health behaviour and lifestyle. Each follow-up questionnaire also recorded the participant's health status. The questionnaires are available at www.e3n.fr .

The questionnaires are anonymous and identified with an identification number and pin code that can be rapidly scanned to identify the respondents. The questionnaires are optically scanned and all answers are checked on screen. The scanned images are saved to allow data entry at a later time, including information regarding the addresses of medical doctors (18 000 to date) or drug names (pre-listed to avoid errors). The longitudinal data (repeats of identical questions for the purpose of updating information about topics such as menopause or smoking) are routinely homogenized. Several validation studies (e.g. dietary and anthropometrical data studies) have been performed and have revealed very satisfactory results.

Self-reported cases of cancer are validated and coded after reviewing the pathology reports obtained from medical practitioners, and nearly 90% of all cancer cases are histologically confirmed. Other diseases are also validated (e.g. diabetes, myocardial infarction, stroke, Parkinson disease) by requesting additional information about the participants (e.g. glycosylated haemoglobin levels, fracture-related circumstances, drug names) and sending questionnaires to medical doctors.

Additionally, a biological material bank was generated. Blood samples were initially collected from 1994-99. The participation rate among the invited participants was approximately 40%; this yielded approximately 25 000 blood samples that were each separated into 28 aliquots (e.g. plasma, serum, leukocytes, erythrocytes). Plastic straws were used to store each participant's samples in liquid nitrogen containers. The bio-repositories are located at the IARC (Lyon) and the EFS (Etablissement Français du Sang, Annemasse). Since 2004, approximately 10 case-control studies have been conducted (approximately 1 800 cases and 3 500 controls) with regard to the measurements of various biomarkers (e.g. fatty acids, calcium, vitamin D, vitamin B, cholesterol and C-reactive protein). A metabolomics study is currently ongoing.

From 2009-11, saliva samples (Oragene, DNA Genotek, Kanata, ON, Canada) were requested from 68 242 living women and were obtained from 47 000 women (participation rate, 69%). Salivary DNA has been extracted and has been used for genotyping in two case-control studies (approximately 2 500 cases and 850 controls) since December 2010.

The research team is currently planning to set up a tumour tissue bank and will begin with the collection of breast cancer tissues.

What has it found? The E3N cohort has produced a spectrum of results regarding the complex roles played by nutrition, hormonal factors, physical activity, anthropometric characteristics and other major lifestyle-related factors with respect to various diseases.

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Conditions studied

  • Breast Cancer
  • Colo-rectal Cancer
  • Parkinson Disease
  • Asthma
  • Diabetes
  • Inflammatory Bowel Diseases
  • Melanoma
  • Endometriosis
  • Thyroid Cancer
  • Hypertension
  • Endometrial Cancer
  • Crohn Disease
  • Depression
  • Cardiovascular Diseases
03

Who can participate

Ages eligible
40 Years and older
Sexes eligible
Female
Accepts healthy volunteers
Yes
Sampling method
Probability sample

Study population

The cohort comprised nearly 100 000 women with baseline ages ranging from 40 to 65 years, all insured through a French national health system (MGEN).

Inclusion criteria

  • only women
  • born between 1925 and 1950
  • insured by the Mutuelle Générale de l'Education Nationale (MGEN)

Exclusion criteria

Exclusion Criteria:

- men

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Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
100,000 participants (actual)
Patient registry
No
Biospecimen retention
Samples with dna
05

What researchers measure

Primary outcomes

  1. Anthropometric measurements

    Height, weight, hip circumference and waist circumference

    Time frame: From 1990 until now

  2. Educational level

    Time frame: 1990

  3. Professional activity

    Insee categories

    Time frame: 1992 and 2005

  4. Age at cessation of activity

    Time frame: From 2005 until now

  5. Menstrual factors

    Age at menarche, length of menstrual cycle

    Time frame: From 1990 to 2002

  6. Reproductive history

    Number of pregnancies, age at each pregnancy, durations and outcomes of pregnancies, breastfeeding, infertility

    Time frame: From 1990 to 1992

  7. Menopause

    Age, type

    Time frame: 1990, 1995, 1997, 2000, 2002, 2005

  8. Hormonal Treatments

    Menopausal Hormonal Treatments (MHT), oral contraceptives

    Time frame: From 1992 to 2008

  9. Tobacco consumption

    Type, quantity, time of smoking

    Time frame: From 1990 until now

  10. Alcohol consumption

    Type of alcohol, quantity

    Time frame: 1993, 1997, 2005

  11. Physical activity

    Moderate and intense activity, sedentarity

    Time frame: 1990,1997,2002, 2005, 2014

  12. Diet questionnaire

    Precise annual diet questionnaire

    Time frame: 1993 and 2002

  13. Family history of diseases

    Cancer, diabetes and cardiovascular diseases

    Time frame: 1990 to 2005

  14. Medication use

    linked with the drug reimbursement files from the health insurance

    Time frame: From 1990 until now

  15. Medical and surgical history

    Time frame: From 1990 until now

  16. Mental Health

    Centre for Epidemiologic Studies Depression Scale (CESD) and Depression

    Time frame: From 1990 until now

  17. Health outcomes

    Time frame: From 1990 until now

06

Study locations

1 site
  • Villejuif, 94800, France
07

References and documents

Publications

  • Clavel-Chapelon F; E3N Study Group. Cohort Profile: The French E3N Cohort Study. Int J Epidemiol. 2015 Jun;44(3):801-9. doi: 10.1093/ije/dyu184. Epub 2014 Sep 10. PubMed 25212479 ↗
  • Danjou AMN, Coudon T, Praud D, Leveque E, Faure E, Salizzoni P, Le Romancer M, Severi G, Mancini FR, Leffondre K, Dossus L, Fervers B. Long-term airborne dioxin exposure and breast cancer risk in a case-control study nested within the French E3N prospective cohort. Environ Int. 2019 Mar;124:236-248. doi: 10.1016/j.envint.2019.01.001. Epub 2019 Jan 16. PubMed 30658268 ↗
  • Lajous M, Boutron-Ruault MC, Fabre A, Clavel-Chapelon F, Romieu I. Carbohydrate intake, glycemic index, glycemic load, and risk of postmenopausal breast cancer in a prospective study of French women. Am J Clin Nutr. 2008 May;87(5):1384-91. doi: 10.1093/ajcn/87.5.1384. PubMed 18469262 ↗
  • Fournier A, Cairat M, Severi G, Gunter MJ, Rinaldi S, Dossus L. Use of menopausal hormone therapy and ovarian cancer risk in a French cohort study. J Natl Cancer Inst. 2023 Jun 8;115(6):671-679. doi: 10.1093/jnci/djad035. PubMed 36809347 ↗
  • Paoletti X, Clavel-Chapelon F. Induced and spontaneous abortion and breast cancer risk: results from the E3N cohort study. Int J Cancer. 2003 Aug 20;106(2):270-6. doi: 10.1002/ijc.11203. PubMed 12800205 ↗
  • Clavel-Chapelon F; E3N-EPIC Group. Differential effects of reproductive factors on the risk of pre- and postmenopausal breast cancer. Results from a large cohort of French women. Br J Cancer. 2002 Mar 4;86(5):723-7. doi: 10.1038/sj.bjc.6600124. PubMed 11875733 ↗
  • Fournier A, Berrino F, Riboli E, Avenel V, Clavel-Chapelon F. Breast cancer risk in relation to different types of hormone replacement therapy in the E3N-EPIC cohort. Int J Cancer. 2005 Apr 10;114(3):448-54. doi: 10.1002/ijc.20710. PubMed 15551359 ↗
  • Fournier A, Fabre A, Mesrine S, Boutron-Ruault MC, Berrino F, Clavel-Chapelon F. Use of different postmenopausal hormone therapies and risk of histology- and hormone receptor-defined invasive breast cancer. J Clin Oncol. 2008 Mar 10;26(8):1260-8. doi: 10.1200/JCO.2007.13.4338. PubMed 18323549 ↗
  • Dusser P, Nguyen Y, Perrin C, Frenoy P, Mariette X, Boutron-Ruault MC, Severi G, Salliot C, Seror R. Birth length and perinatal exposures and rheumatoid arthritis risk in the E3N cohort. RMD Open. 2026 Apr 9;12(2):e006415. doi: 10.1136/rmdopen-2025-006415. PubMed 41956708 ↗
  • Dusser P, Nguyen Y, Perrin C, Frenoy P, Mariette X, Boutron-Ruault MC, Varraso R, Severi G, Salliot C, Seror R. Early-life animal and farming exposures and the risk of rheumatoid arthritis: findings from the E3N French cohort study. RMD Open. 2025 Dec 7;11(4):e005954. doi: 10.1136/rmdopen-2025-005954. PubMed 41360603 ↗
  • Auguste A, Jansana A, Freisling H, Ferrari P, Laouali N, Severi G, Kvaskoff M. Impact of Hypertension on Cancer Stage at Diagnosis Among French Women: The E3N Prospective Cohort. Cancer Med. 2025 Aug;14(15):e71021. doi: 10.1002/cam4.71021. PubMed 40719276 ↗
  • Klu YE, Amazouz H, Canonico M, Guenel P, Kvaskoff M, Severi G, Radoi L, Auguste A. Association Between Hormonal Factors and Risk of Lung and Upper Aerodigestive Tract Cancer in French Women: The E3N Prospective Cohort Study. Cancer Rep (Hoboken). 2025 Jun;8(6):e70223. doi: 10.1002/cnr2.70223. PubMed 40490966 ↗
  • Koemel NA, Shah S, Senior AM, Severi G, Mancini FR, Gill TP, Simpson SJ, Raubenheimer D, Boutron-Ruault MC, Laouali N, Skilton MR. Macronutrient composition of plant-based diets and breast cancer risk: the E3N prospective cohort study. Eur J Nutr. 2024 Aug;63(5):1771-1781. doi: 10.1007/s00394-024-03379-x. Epub 2024 Apr 18. PubMed 38635026 ↗
  • Shah S, Mahamat-Saleh Y, Ait-Hadad W, Koemel NA, Varraso R, Boutron-Ruault MC, Laouali N. Long-term adherence to healthful and unhealthful plant-based diets and breast cancer risk overall and by hormone receptor and histologic subtypes among postmenopausal females. Am J Clin Nutr. 2023 Mar;117(3):467-476. doi: 10.1016/j.ajcnut.2022.11.019. PubMed 36872016 ↗
  • Shah S, Mahamat-Saleh Y, Hajji-Louati M, Correia E, Oulhote Y, Boutron-Ruault MC, Laouali N. Palaeolithic diet score and risk of breast cancer among postmenopausal women overall and by hormone receptor and histologic subtypes. Eur J Clin Nutr. 2023 May;77(5):596-602. doi: 10.1038/s41430-023-01267-x. Epub 2023 Feb 1. PubMed 36726032 ↗
  • Frenoy P, Perduca V, Cano-Sancho G, Antignac JP, Severi G, Mancini FR. Application of two statistical approaches (Bayesian Kernel Machine Regression and Principal Component Regression) to assess breast cancer risk in association to exposure to mixtures of brominated flame retardants and per- and polyfluorinated alkylated substances in the E3N cohort. Environ Health. 2022 Feb 26;21(1):27. doi: 10.1186/s12940-022-00840-4. PubMed 35216589 ↗
  • Madika AL, MacDonald CJ, Gelot A, Hitier S, Mounier-Vehier C, Beraud G, Kvaskoff M, Boutron-Ruault MC, Bonnet F. Hysterectomy, non-malignant gynecological diseases, and the risk of incident hypertension: The E3N prospective cohort. Maturitas. 2021 Aug;150:22-29. doi: 10.1016/j.maturitas.2021.06.001. Epub 2021 Jun 12. PubMed 34274072 ↗
  • Laouali N, Shah S, MacDonald CJ, Mahamat-Saleh Y, El Fatouhi D, Mancini F, Fagherazzi G, Boutron-Ruault MC. BMI in the Associations of Plant-Based Diets with Type 2 Diabetes and Hypertension Risks in Women: The E3N Prospective Cohort Study. J Nutr. 2021 Sep 4;151(9):2731-2740. doi: 10.1093/jn/nxab158. PubMed 34236437 ↗
  • Cairat M, Al Rahmoun M, Gunter MJ, Severi G, Dossus L, Fournier A. Antiplatelet Drug Use and Breast Cancer Risk in a Prospective Cohort of Postmenopausal Women. Cancer Epidemiol Biomarkers Prev. 2021 Apr;30(4):643-652. doi: 10.1158/1055-9965.EPI-20-1292. Epub 2021 Feb 2. PubMed 33531438 ↗
  • Azevedo Da Silva M, Fournier A, Boutron-Ruault MC, Balkau B, Bonnet F, Nabi H, Fagherazzi G. Increased risk of type 2 diabetes in antidepressant users: evidence from a 6-year longitudinal study in the E3N cohort. Diabet Med. 2020 Nov;37(11):1866-1873. doi: 10.1111/dme.14345. Epub 2020 Jul 2. PubMed 32542873 ↗
  • Mahamat-Saleh Y, Cervenka I, Al Rahmoun M, Savoye I, Mancini FR, Trichopoulou A, Boutron-Ruault MC, Kvaskoff M. Mediterranean dietary pattern and skin cancer risk: A prospective cohort study in French women. Am J Clin Nutr. 2019 Oct 1;110(4):993-1002. doi: 10.1093/ajcn/nqz173. PubMed 31380561 ↗
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Registry details

Key details

Study ID
NCT03285230
Lead sponsor
Institut National de la Santé Et de la Recherche Médicale, France
Collaborators
Université Paris-Sud, Gustave Roussy, Cancer Campus, Grand Paris, Ligue contre le cancer, France
Responsible party
Sponsor
First posted
Sep 15, 2017
Start date
Jun 15, 1990
Primary completion
Nov 15, 1991
Completion
Dec 31, 2046 (estimated)
Last update
Jun 25, 2026

Study contacts

Gianluca Severi, PhD
study director · INSERM (Institut National de la Sante et de la Recherche Medicale)

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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