Abstract:
OBJECTIVES:To investigate the association between contemporary combined hormonal contraceptives (including progestogen types in combined preparations and all progestogen-only products) and overall and specific types of ovarian cancer. DESIGN:Prospective, nationwide cohort study. SETTING:Denmark, 1995-2014. PARTICIPANTS:All women aged 15-49 years during 1995-2014 were eligible. Women were excluded if they immigrated after 1995, had cancer (except non-melanoma skin cancer), had venous thrombosis, or were treated for infertility before entry (final study population included 1 879 227 women). Women were categorised as never users (no record of being dispensed hormonal contraception), current or recent users (≤1 year after stopping use), or former users (>1 year after stopping use) of different hormonal contraceptives. MAIN OUTCOME MEASURES:Poisson regression was used to calculate relative risk of ovarian cancer among users of any contemporary combined hormonal contraceptives and by progestogen type in combined preparations and all progestogen-only products, including non-oral preparations. Separate analyses examined women followed up to their first contraception type switch and those with full contraceptive histories. Duration, time since last use, and tumour histology were examined and the population prevented fraction were calculated. RESULTS:During 21.4 million person years, 1249 incident ovarian cancers occurred. Among ever users of hormonal contraception, 478 ovarian cancers were recorded over 13 344 531 person years. Never users had 771 ovarian cancers during 8 150 250 person years. Compared with never users, reduced risks of ovarian cancer occurred with current or recent use and former use of any hormonal contraception (relative risk 0.58 (95% confidence interval 0.49 to 0.68) and 0.77 (0.66 to 0.91), respectively). Relative risks among current or recent users decreased with increasing duration (from 0.82 (0.59 to 1.12) with ≤1 year use to 0.26 (0.16 to 0.43) with >10 years' use; P<0.001 for trend). Similar results were achieved among women followed up to their first switch in contraceptive type. Little evidence of major differences in risk estimates by tumour type or progestogen content of combined oral contraceptives was seen. Use of progestogen-only products were not associated with ovarian cancer risk. Among ever users of hormonal contraception, the reduction in the age standardised absolute rate of ovarian cancer was 3.2 per 100 000 person years. Based on the relative risk for the never use versus ever use categories of hormonal contraception (0.66), the population prevented fraction was estimated to be 21%-that is, use of hormonal contraception prevented 21% of ovarian cancers in the study population. CONCLUSIONS:Use of contemporary combined hormonal contraceptives is associated with a reduction in ovarian cancer risk in women of reproductive age-an effect related to duration of use, which diminishes after stopping use. These data suggest no protective effect from progestogen-only products.
journal_name
BMJjournal_title
BMJ (Clinical research ed.)authors
Iversen L,Fielding S,Lidegaard Ø,Mørch LS,Skovlund CW,Hannaford PCdoi
10.1136/bmj.k3609subject
Has Abstractpub_date
2018-09-26 00:00:00pages
k3609eissn
0959-8138issn
1756-1833journal_volume
362pub_type
杂志文章abstract:OBJECTIVE:To determine prevalence of HIV infection and drug injecting behaviour among inmates of Glenochil Prison on a specified date a year after an outbreak of hepatitis B and HIV infection. DESIGN:Cross sectional: voluntary, anonymous HIV salivary antibody surveillance and linked self completion questionnaire on ri...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.310.6975.293
更新日期:1995-02-04 00:00:00
abstract:OBJECTIVE:To compare the effectiveness of classroom based cognitive behavioural therapy with attention control and usual school provision for adolescents at high risk of depression. DESIGN:Three arm parallel cluster randomised controlled trial. SETTING:Eight UK secondary schools. PARTICIPANTS:Adolescents (n=5030) ag...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,随机对照试验
doi:10.1136/bmj.e6058
更新日期:2012-10-05 00:00:00
abstract::A total of 563 white primigravid patients at Raigmore Hospital, Inverness, were recruited in a prospective study to examine the association between maternal height, shoe size, and the outcome of labour. There was a significantly increased caesarean section rate in women of short stature but no association between mode...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.297.6647.515
更新日期:1988-08-20 00:00:00
abstract:OBJECTIVE:To confirm the findings of pilot studies that interferon alfa is an effective treatment of Europid men with chronic hepatitis B virus infection. DESIGN:Randomised controlled trial of three months treatment with interferon alfa followed by 12 months of observation. SETTING:Outpatient clinic of a tertiary ref...
journal_title:BMJ (Clinical research ed.)
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1136/bmj.299.6700.652
更新日期:1989-09-09 00:00:00
abstract:OBJECTIVE:To determine the global capacity (availability, accessibility, quality, and affordability) to deliver kidney replacement therapy (dialysis and transplantation) and conservative kidney management. DESIGN:International cross sectional survey. SETTING:International Society of Nephrology (ISN) survey of 182 cou...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.l5873
更新日期:2019-10-31 00:00:00
abstract:OBJECTIVES:To assess the effects of treatments for non-metastatic invasive squamous cell carcinoma (SCC) of the skin using evidence from observational studies, given the paucity of evidence from randomised controlled trials. DESIGN:Systematic review of observational studies. DATA SOURCES:Medline, Embase, to December ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,meta分析,评审
doi:10.1136/bmj.f6153
更新日期:2013-11-04 00:00:00
abstract::A US organization, Population Action International, is reported in this article to have released findings on the health risks for women in 118 countries. Countries are ranked on 10 indicators, including such indicators as the number of births to women aged under 19 years, the availability of legal abortion, maternal ...
journal_title:BMJ (Clinical research ed.)
pub_type: 新闻
doi:10.1136/bmj.311.6998.147a
更新日期:1995-07-15 00:00:00
abstract:OBJECTIVE:To study the association between number of cups of coffee consumed per day and coronary death when taking other major coronary risk factors into account. DESIGN:Men and women attending screening and followed up for a mean of 6.4 years. SETTING:Cardiovascular survey performed by ambulatory teams from the Nat...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.300.6724.566
更新日期:1990-03-03 00:00:00
abstract:OBJECTIVE:To observe the effects of stimulation of the sacral anterior roots on anorectal and low colonic pressures and to programme implanted stimulators to produce defecation. DESIGN:Prospective study of 12 consecutive patients. SETTING:Spinal injuries unit and university gastrointestinal physiology department. PA...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.300.6738.1494
更新日期:1990-06-09 00:00:00
abstract:OBJECTIVE:To assess the direct and indirect effects of being a twin, maternal smoking, birth weight, and mother's height on blood pressure at ages 9 and 18 years. DESIGN:Longitudinal study. SUBJECTS:Cohort born in 1972-3. SETTING:Dunedin, New Zealand. MAIN OUTCOME MEASURE:Blood pressure at ages 9 and 18 years. RES...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.318.7188.897
更新日期:1999-04-03 00:00:00
abstract:OBJECTIVE:To examine the patterns of physical activity among British schoolchildren aged 11 to 16 and to assess whether the children experience the intensity and duration of physical activity that are believed to stress the cardiopulmonary system appropriately. DESIGN:Cross sectional study of a sample of children draw...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.301.6745.203
更新日期:1990-07-28 00:00:00
abstract:OBJECTIVES:To examine the risk of atrial fibrillation in relation to the whole spectrum of thyroid function in a large cohort of patients. DESIGN:Population based cohort study of general practice patients identified by linkage of nationwide registries at the individual level. SETTING:Primary care patients in the city...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.e7895
更新日期:2012-11-27 00:00:00
abstract:OBJECTIVE:To describe the characteristics of patients using non-orthodox health care and their pattern of use of conventional health care with respect to a particular problem. DESIGN:Postal survey of all 2152 practitioners of acupuncture, chiropractic, homeopathy, naturopathy, and osteopathy identified from 11 nationa...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.302.6770.207
更新日期:1991-01-26 00:00:00
abstract:OBJECTIVE:To investigate the association between cerebral palsy and direct evidence for perinatal exposure to neurotropic viruses. DESIGN:Population based case-control study. SETTING:Adelaide Women's and Children's Hospital Research Laboratory. PARTICIPANTS AND MAIN OUTCOME MEASURES:Newborn screening cards of 443 wh...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.38668.616806.3A
更新日期:2006-01-14 00:00:00
abstract:OBJECTIVES:To determine the accuracy of a clinical decision rule (the traffic light system developed by the National Institute for Health and Clinical Excellence (NICE)) for detecting three common serious bacterial infections (urinary tract infection, pneumonia, and bacteraemia) in young febrile children. DESIGN:Retro...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.f866
更新日期:2013-02-13 00:00:00
abstract::Elderly and disabled people have been led to expect great improvements in the quality of community care after April 1993. The choice to live safely at home is to be offered as an alternative to residential care. The financial and organisational relationships are all intended to support this in practice. The Tomlinson ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.305.6866.1418
更新日期:1992-12-05 00:00:00
abstract:OBJECTIVES:To document the extent to which maternity data are collected and how they are recorded, and to identify problems that may affect their availability throughout the NHS. METHODS:Postal survey in September 1997 with structured questionnaires. SETTING:207 NHS trusts with maternity units in England. PARTICIPAN...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.319.7210.619
更新日期:1999-09-04 00:00:00
abstract::A study was carried out analysing the operation of a drug rationalisation programme in a central London teaching district that had evolved from experience over 17 years. Creation of a limited list of about 700 drugs had been achieved by local consensus. Drug selection was based on appraisal of efficacy, safety, and co...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.297.6646.465
更新日期:1988-08-13 00:00:00
abstract:OBJECTIVE:To study the circumstances of dog bites and identify risk factors. DESIGN:Postal questionnaire survey and case note review of victims of dog bites referred between 1982 and 1989. SETTING:One referral based regional plastic surgery unit. PATIENTS:146 consecutive patients referred for primary treatment of do...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.303.6816.1512
更新日期:1991-12-14 00:00:00
abstract:OBJECTIVE:To assess the accuracy of the AbC-19 Rapid Test lateral flow immunoassay for the detection of previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. DESIGN:Test accuracy study. SETTING:Laboratory based evaluation. PARTICIPANTS:2847 key workers (healthcare staff, fire and rescue of...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.m4262
更新日期:2020-11-11 00:00:00
abstract:OBJECTIVE:To investigate the clinical effects of regulating umbilical cord clamping in preterm infants. DESIGN:A prospective randomised study. SETTING:The Queen Mother's Hospital, Glasgow. SUBJECTS:36 vaginally delivered infants over 27 and under 33 weeks' gestation. INTERVENTION:Holding the infant 20 cm below the ...
journal_title:BMJ (Clinical research ed.)
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1136/bmj.306.6871.172
更新日期:1993-01-16 00:00:00
abstract:OBJECTIVE:To determine the long term effects of antibiotic treatment for acute otitis media in young children. DESIGN:Prospective three year follow-up study within the framework of a primary care based, double blind, randomised, placebo controlled trial. SETTING:53 general practices in the Netherlands. PARTICIPANTS:...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1136/bmj.b2525
更新日期:2009-06-30 00:00:00
abstract:OBJECTIVES:To compare mix of patients, scope of practice, and duration of visit in primary care physicians in Australia, New Zealand, and the United States. DESIGN:Comparison of three comparable cross sectional surveys performed in 2001-2. Physicians completed a questionnaire on patients' demographics, diagnoses, and ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,多中心研究
doi:10.1136/bmj.39203.658970.55
更新日期:2007-06-16 00:00:00
abstract::The results of a survey of 769 patients attending the St. James's University Fertility Control Clinic, England, for abortion services showed that patients seeing general practitioners were less knowledgeable than those attending specialist clinics. There was a demonstrated need for counseling on pill and condom use a...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.306.6877.556
更新日期:1993-02-27 00:00:00
abstract:OBJECTIVE:To investigate the effects of the home environment on the risk of severe asthma during adolescence. DESIGN:A questionnaire based case-control study drawn from a cross sectional survey of allergic diseases among secondary school pupils in Sheffield in 1991. SUBJECTS:763 children whose parents had reported th...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.311.7012.1053
更新日期:1995-10-21 00:00:00
abstract:OBJECTIVE:To determine whether screening Danish men aged 65 or more for abdominal aortic aneurysms reduces mortality. DESIGN:Single centre randomised controlled trial. SETTING:All five hospitals in Viborg County, Denmark. PARTICIPANTS:All 12,639 men born during 1921-33 and living in Viborg County. In 1994 we include...
journal_title:BMJ (Clinical research ed.)
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1136/bmj.38369.620162.82
更新日期:2005-04-02 00:00:00
abstract:OBJECTIVES:To assess whether blood pressure control in primary care could be improved with the use of patient held targets and self monitoring in a practice setting, and to assess the impact of these on health behaviours, anxiety, prescribed antihypertensive drugs, patients' preferences, and costs. DESIGN:Randomised c...
journal_title:BMJ (Clinical research ed.)
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1136/bmj.38558.393669.E0
更新日期:2005-09-03 00:00:00
abstract:OBJECTIVE:To assess the risk of cerebral thromboembolism in women using low dose oral contraceptives. DESIGN:A retrospective case-control study. SETTING:All Danish medical, neurological, neurosurgical, and gynaecological departments. SUBJECTS:All 794 women in Denmark aged 15-44 who had suffered a cerebral thromboemb...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.306.6883.956
更新日期:1993-04-10 00:00:00
abstract:OBJECTIVE:To determine whether the variation in unadjusted rates of caesarean section derived from routine data in NHS trusts in England can be explained by maternal characteristics and clinical risk factors. DESIGN:A cross sectional analysis using routinely collected hospital episode statistics was performed. A multi...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,多中心研究
doi:10.1136/bmj.c5065
更新日期:2010-10-06 00:00:00
abstract:OBJECTIVE:To assess and compare the accuracy of visual inspection with acetic acid (VIA), visual inspection with Lugol's iodine (VILI), and human papillomavirus (HPV) testing as alternative standalone methods for primary cervical cancer screening in sub-Saharan Africa. DESIGN:Systematic review and meta-analysis of dia...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,meta分析,评审
doi:10.1136/bmj.h3084
更新日期:2015-07-03 00:00:00