Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.

Of 47,000 women followed since 1968, those who had used oral contraceptives (ever-users) had a significantly higher incidence rate of cervical cancer than never-users. After standardisation of rates by age, parity, smoking, social class, number of previously normal cervical smears, and history of se...

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Main Authors: Beral, V, Hannaford, P, Kay, C
Format: Journal article
Language:English
Published: 1988
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author Beral, V
Hannaford, P
Kay, C
author_facet Beral, V
Hannaford, P
Kay, C
author_sort Beral, V
collection OXFORD
description Of 47,000 women followed since 1968, those who had used oral contraceptives (ever-users) had a significantly higher incidence rate of cervical cancer than never-users. After standardisation of rates by age, parity, smoking, social class, number of previously normal cervical smears, and history of sexually transmitted disease, the excess was 41 per 100,000 woman-years for carcinoma-in-situ and 8 per 100,000 woman-years for invasive cervical cancer. Incidence increased with increasing duration of use: the standardised incidence rate for cervical cancer in women who had taken the pill for more than 10 years was four times than in never-users. Ever-users had a lower incidence of other uterine cancers (deficit 5 per 100,000 woman-years); a lower incidence of ovarian cancer was also found (deficit 4 per 100,000), but was not statistically significant. Overall, ever-users had an excess incidence for genital tract cancers 37 per 100,000 woman-years. This excess was mainly from carcinoma-in-situ of the cervix; the excess incidence of invasive cervical cancer was offset by the deficits in other uterine and ovarian cancers. Standardised mortality rates from genital cancer were similar in ever-users and never-users. Of relevance to clinical practice is the substantially different distribution of primary cancer sites: cervical cancer accounted for 75% of the invasive genital cancers and 74% of deaths from genital cancer in ever-users, but only 31% of the invasive cancers and 30% of deaths in never-users.
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spelling oxford-uuid:a4ab8d20-8aa0-4c62-8821-61bb6c9872cf2022-03-27T02:35:23ZOral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:a4ab8d20-8aa0-4c62-8821-61bb6c9872cfEnglishSymplectic Elements at Oxford1988Beral, VHannaford, PKay, COf 47,000 women followed since 1968, those who had used oral contraceptives (ever-users) had a significantly higher incidence rate of cervical cancer than never-users. After standardisation of rates by age, parity, smoking, social class, number of previously normal cervical smears, and history of sexually transmitted disease, the excess was 41 per 100,000 woman-years for carcinoma-in-situ and 8 per 100,000 woman-years for invasive cervical cancer. Incidence increased with increasing duration of use: the standardised incidence rate for cervical cancer in women who had taken the pill for more than 10 years was four times than in never-users. Ever-users had a lower incidence of other uterine cancers (deficit 5 per 100,000 woman-years); a lower incidence of ovarian cancer was also found (deficit 4 per 100,000), but was not statistically significant. Overall, ever-users had an excess incidence for genital tract cancers 37 per 100,000 woman-years. This excess was mainly from carcinoma-in-situ of the cervix; the excess incidence of invasive cervical cancer was offset by the deficits in other uterine and ovarian cancers. Standardised mortality rates from genital cancer were similar in ever-users and never-users. Of relevance to clinical practice is the substantially different distribution of primary cancer sites: cervical cancer accounted for 75% of the invasive genital cancers and 74% of deaths from genital cancer in ever-users, but only 31% of the invasive cancers and 30% of deaths in never-users.
spellingShingle Beral, V
Hannaford, P
Kay, C
Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title_full Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title_fullStr Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title_full_unstemmed Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title_short Oral contraceptive use and malignancies of the genital tract. Results from the Royal College of General Practitioners' Oral Contraception Study.
title_sort oral contraceptive use and malignancies of the genital tract results from the royal college of general practitioners oral contraception study
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AT kayc oralcontraceptiveuseandmalignanciesofthegenitaltractresultsfromtheroyalcollegeofgeneralpractitionersoralcontraceptionstudy