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Contraceptive Pill side-effects

chemist dispensing the pill






Chemist dispensing the pill

A Fact Sheet

  1. Breast Cancer

    • For those women starting the pill before 20yrs old, the risk of developing breast cancer was 820% higher than for healthy non-users of the same age.(Reference 1)
    • For women starting pill between 20-25 years, relative risk was 180% higher than healthy non-users (Ref 1)
    • Other researchers cite the risk of breast cancer for young women(less than 20 yrs old) is 200-480% higher than for non-pill users(Refs 2,3,4)
    • In one study of 918 Dutch women diagnosed with invasive breast cancer, 85% had used the pill at some time (5)
    • Even 3 months use of the pill has been reported to be associated with 100% increase in breast cancer (6)
    • For more than ten years use, breast cancer risk increased by 310% (7)
    • women with breast cancer, who at an early age have used oral contraceptives, have larger breast tumours and a worst prognosis compared with later(pill users) and never users(8)
    • Death rate from breast cancer in

      Australia = 20.4/100,000
      USA = 20.7/100,000
      Japan = 7.1/100,000

      ie a x3 fold reduction in Japan. Australia/USA have a pill history of 30 years with identical breast cancer statistics. Industrialised Japan, has no pill use, reports one third the rate (9)

    • (Note: With use of Depo-Provera (DMPA) "Use for two years or longer before age 25 was associated with a significantly increased risk of breast cancer" (ie 360% increase) (10)

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  2. Cervical Cancer

    • Pill use in women less than 20years old means 280% higher risk of cervical cancer
    • In women 20-24 years, its 70 % higher.
    • In women 25-29 years its 40% higher (11)
    • Another study cites increased risk of 250% for cervical cancer amongst pill users (12)
    • Longer term users(6-12 years) 100-340% increased risk of non-users cervical cancer(13,14)
    • However, one of these studies showed women who used the pill for only 1-6 months had a 190% increase in cervical cancer than non-users (15)
    • Clinical evidence cites the pill’s role in activation of and enhancing HPV (Human Papilloma Virus) in initiation of cervical cancer. (16,17)

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  3. Deep Vein Thrombosis (DVT)
    • Risk of DVT increased by 600-900%(ie 5-8 fold) compared to non-users in users of 3rd generation progestagen pills (eg containing gestodene eg Femodene, Minulet, Tri-minulet, or containing desogestrel eg Marvelon) (18,19)
    • Across all age groups, use of the 3rd generation pill brands had a 770% greater DVT risk than non-pill users (20)
    • Second generation progestagens such as levonorgestrel and norethisterone have 120-280% increase risk of DVT (21,22)
    • For teenagers aged 15-19yrs risk of DVT " for the desogestrel-containing oral contraceptive was 7-fold higher than that of the levo-norgestrel containing products; among women aged 20-24 the risk was 4-fold higher" (23) IMPORTANT! Note that this x7 increase was relative to 2nd generation users not non-users!! Therefore, by computation, risk for 15-19yr olds compared to non-users is (120%-280%) x 7 = x 15-26 fold risk!!
    • A x50 fold increase risk of DVT for users carrying a blood clotting factor V Leiden mutation.This occurs in 5-15% of European women(26) Note mechanism gestodene causes decreased oestrogen metabolism in liver leading to accumulation in body leading to increased DVT risk.

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  4. Infertility after pill-use

    Women may not conceive for up to 48 months or longer depending on age This is due to atrophy of the mucus secreting glands thus preventing sperm transport.

  5. Teratogenicity

     Birth defects/chromosomal abnormalities in children conceived right after pill cessation.

  6. Author's Comment

     Fertility drugs cause hyperstimulation of the ovaries, leading to increased ovarian cancer of the ovary due to increased minor trauma of the covering epilthelium The pill, and pregnancy, and breast feeding cause a rest in ovulation, thus associated with a decreased incidence of ovarian cancer. Some family planning advocates defend or advocate pill use because of the associated decrease in ovarian cancer rates(0.2% risk). To do so in light of the appalling side-effects of the pill documented is a woeful ignorance of the facts or a deliberate and cynical act of injustice to women.

  7. References

     All references from:
    "A Consumer’s Guide to the Pill" by John Wilks B Pharm MPS 2nd Ed 1997
    ALL Publications available from HLI Ireland £10.99 + £2.00 p+p

    1. Olsson H, Borg A, Ferno M, Moller TR, Ranstam J. Early oral contraceptive use and premenopausal breast cancer – a review of studies performed in South Sweden Cancer Detection and Prevention 1991:15 (4): 265-271 Table IV.

    2. Olsson H & ML, Moller TR, Ranstam J, Holm P. Lancet(letter) 1985 March 30, 748-49.

    3. Olsson H, Moller TR, Ranstam J. Early oral contraceptive use and breast cancer among premenopausal women: Final report from a study in Southern Sweden. Journal of the National Cancer Institute. 1989;81(12):1000-4.

    4. Johnson JH, Weighing the evidence on the pill and breast cancer Family Planning Perspectives 1989: 21 (2): 89-92.

    5. Rookus & Van Leeuwen. Oral Contraceptives and risk of Breast Cancer women aged 20-54 years. Lancet 1994 ; 344; p844-51.

    6. Millar DR, Rosenberg L, et al Breast Cancer before age 45 and oral contraceptive use ; new findings. American J of Epidemiology 1989;129 (2):269- 80.

    7. Millar, 1989 as above.

    8. Olsson H, Borg A, ferno M, Moller T, Ranstam J. Early oral contraceptive use and breast cancer in Southern Sweden. Proc. Annu Meet Am Soc Clin Oncol. 1989: A367, Ma.

    9. WHO Cancer Mortality database 1994 Breast Cancer Rates by Country. Paul C, Depo medroxyprogesterone (Depo-Provera) and risk of breast cancer Br Med J 1989; 299: p762.

    10. Thomas DB, Ray RM. Oral contraceptives and invasive adenocarcinomas and adenosquamous carcinomas of the uterine cervix Am J Epid 1996;144:p284 table 2.

    11. Kohler U, Wuttke P. results of a case control study of the current effect of various factors of cervical cancer risk . 2) Contraceptive behaviour and the smoking factor. Zentralblatt fur gynakologie 1994;116 (7): 405- 9 (Ma).

    12. Ursin G, Peters RK, Henderson BE, d’Ablaing G, Monroe KR, Pike MC. Oral contraceptive use and adenocarcinoma of cervix. Lancet 1994; 344; 1390-1394.

    13. Brisson J et al Risk factors for cervical Intraepithelial Neoplasia: differences between low and high-grade lesions American J of Epidemiology 1994;140:700-710.

    14. Ursin et al, 1994 as above.

    15. Chen Y-H, Huang L-H, Chen T-M. Differential effects of progestins and estrogens on long control regions of human papilloma virus types 16 and 18. Biochemical and Biophysical Research Communications 1996;224:p654.

    16. Kenney JAW. Risk Factors associated with genital HPV infection. Cancer Nurse 1996 (Oct);19:5, p353.

    17. Vandebrouke JP, Rosendaal FR. End of the line for "third-generation pill" controversy? Lancet 1997; 349:1113-1114.

    18. Vandebrouke JP et al Increased risk of venous thrombosis in oral contraceptive users who are carriers of factor V Leiden mutation. Lancet 1994;344:p 1454.

    19. Bloemenkamp KW, Rosendal FR, Helmerhorst FM, Bauller HR, Vandenbroche JP. Enhancement by factor V Leiden mutation of deep vein thrombosis associated with oral contraceptives containing third generation progestogen. Lancet 1995;346:8990:1593-6.

    20. Bloemenkamp et al, p1594, table 1.

    21. Spitzer WO, Lewis MA, Heineman LAJ et al. Third generation oral contraceptives and risk of venous thromboembolic disorders: an international case-control study Br Med J 1996;312:83-8.

    22. Bloemenkamp et al p1595.

    23. Vandebrouke JP et al 1997.

    24. Bloemenkamp et al p1593.

    25. Sarisin,F Bounameaux,H Decision analysis model of prolonged oral anticoagulant treatment in factor V Leiden carriers with first episode of deep vein thrombosis. Br Med J.1998:316;95.

    26. APPG 24th Ed Microgynon 30 monograph 1995 p1508.

    27. Micromedex vol 89 Oral contraceptives monograph.

    28. Wade ME, McCarthy PM et al. Am J Obstet Gynaecol 1995; 172: p698.

    29. Rahwan R, Prof Pharmacology & Toxicology, College of Pharmacy Ohio State University. Chemical Contraceptives, Interceptives and Abortifacients 1995.


      30. Patrick McCrystal
      Human Life International (Ireland)
      Jan 1999

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