ORAL CONTRACEPTIVES
- OC and cardiovascular disease
- OC and breast cancer
- OC and other types of cancer
- OC and miscellaneous
Note: The information on this website is not a substitute for
diagnosis and treatment by a qualified, licensed professional.
Mortality associated with oral contraceptive use
25 year follow up of cohort of 46 000 women from Royal College of General Practitioners' oral contraception study.
Beral V, et al.
BMJ 1999;318:96-100 ( 9 January ).The results of this study, conducted on 46,000 women followed-up for 25 years, show that users of oral contraceptives have a 2.5 increased risk of death from cancer of the uterine cervix, a twofold increased risk of death from cerebrovascular diseases, and a 5-fold increased risk of death from liver cancer compared to nonusers. Use of oral contraceptives is associated with an 80% decreased risk of death from ovarian cancer. The adverse effects on mortality persisted for 10 years after interruption of oral contraceptive intake, and ceased afterwards.
Acute myocardial infarction and combined oral contraceptives
Results of an international multicentre case-control study. WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Lancet, 349(9060):1202-9 1997 Apr 26.The results of this study show that women aged 20-44 years taking oral contraceptives (OCs) have a 5-fold increased risk of myocardial infarction (MI), compared to nonusers. Women taking oral contraceptives and smoking 10 or more cigarettes per day have an over 20-fold increased risk of myocardial infarction, compared to those with neither risk factor. Use of OCs in women with a history of hypertension during pregnancy or at any other time is associated with an over 10-fold increased risk of MI. The risk seems to remain constant throughout duration of OC use, and no longer persists after discontinuation of use.
Risk of idiopathic cardiovascular death and nonfatal venous thromboembolism in women using oral contraceptives with differing progestagen components.
Jick H, Jick SS, Gurewich V, Myers MW, Vasilakis C.
Lancet, 346(8990):1589-93 1995 Dec 16.The results of this study show that users of oral contraceptives (OC) of the third generation containing gestodene or desogestrel, have a 40% and 60% increased risk of dying from cardiovascular disease, respectively, compared to users of OC of the second generation containing levonorgestrel. In addition, use of the third generation progestins desogestrel and gestodene was found to be associated with a 90% and 80% increased risk of deep venous thrombosis and pulmonary embolism, respectively, compared to use of the older pills containing the progestin levonorgestrel.
Estimates of the risk of cardiovascular death attributable to low-dose oral contraceptives in the United States.
Schwingl PJ, Ory HW, Visness CM.
Am J Obstet Gynecol 1999 Jan;180(1 Pt 1):241-9.This study estimated that in the U.S., use of oral contraceptives in women who do not smoke is associated with a risk of 0.06 deaths from cardiovascular disease per 100,000 users aged 15-34, and with 3 deaths per 100,000 users aged 35-44. In women who smoke, oral contraceptive use is associated with a risk of 1.73 and 19.4 deaths from cardiovascular disease per 100,000 users aged 15-34 and 35-44, respectively. In women older than 35 who smoke and take oral contraceptives, the risk of death from cardiovascular disease is higher than the risk of death from pregnancy complications.
Oral contraceptives and fatal pulmonary embolism.
Parkin L, Skegg DCG, Wilson M, Herbison GP, Paul C.
Lancet 2000; 355: 2088,2133 - 2134.The results of this study show that women of childbearing age using combined oral contraceptives have an almost 10-fold higher risk of dying from pulmonary embolism, compared to nonusers. The finding of a substantial increased risk of this fatal complication in users of oral contraceptives is especially important when considering that these deaths occur in healthy young women who would have otherwise had a long life expectancy ahead of them.
Ischemic Stroke Risk With Oral Contraceptives. A Meta-analysis.
Gillum LA, Mamidipudi SK, and Johnston SC.
JAMA 2000;284:72-78.The results of this study, a meta-analysis of 16 trials investigating the relationship between oral contraceptive use and ischemic stroke, show that users of oral contraceptives have a 2.75-fold higher risk of ischemic stroke, compared to nonusers. The risk increases with increasing doses of estrogens contained in the pill, from a 2-fold increase in users of low-dose estrogen preparations, to a 4.5-fold increase in users of more than 50 micrograms of estrogen. This excess risk translates in 1 extra ischemic stroke per year for every 24,000 women using oral contraceptives. These data indicate that contrary to what previously believed, users of lower-dose estrogens are not spared from the excess risk of stroke associated with oral contraceptives.
Case-control study of oral contraceptives and risk of thromboembolic stroke: results from international study on oral contraceptives and health of young women
Heinemann LAJ, et al.
BMJ 1997;315:1502-1504 (6 December).The results of this study show that women aged 16-44 years using first, second, and third generation oral contraceptives have a 4.4-, 3.4-, and 3.9-fold increased risk of developing ischaemic stroke, compared to nonusers.
Ischaemic stroke and combined oral contraceptives
Results of an international, multicentre, case-control study. WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Lancet 1996 Aug 24;348(9026):498-505.The results of this study show that use of oral contraceptives is associated with a 3-fold increased risk of ischemic stroke in women aged 22-44 years. The presence of high blood pressure further increases the risk, and hypertensive women taking oral contraceptives were found to have an almost 11-fold increased risk of stroke in Europe and a 14.5-fold increased risk of stroke in Africa, Asia, or South America.
Haemorrhagic stroke, overall stroke risk, and combined oral contraceptives
Results of an international, multicentre, case-control study. WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Lancet 1996 Aug 24;348(9026):505-10.The results of this study show that use of oral contraceptives is associated with an over 2-fold increased risk of haemorrhagic stroke in women aged 35 years and older. Women with a history of hypertension using oral contraceptives have a 10- to 15-fold increased risk of hemorrhagic stroke, compared to women with neither risk factor, while the risk increases by 3-folds in women who smoke and take oral contraceptives. The authors estimated that use of oral contraceptives is responsible for 13% and 8% of all strokes occurring among women aged 20-44 years in Europe and in the developing countries, respectively.
Migraine and stroke in young women: case-control study. The World Health Organisation Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Chang CL, Donaghy M, Poulter N.
BMJ 1999 Jan 2;318(7175):13-8.The results of this study show that the risk of stroke in women with migraines is significantly increased in users of oral contraceptives. The study first demonstrated a 3.5-fold increased of ischemic stroke in women with migraines, compared to the general population. Secondly, the study showed that oral contraceptives, high blood pressure or smoking had a greater than multiplicative effect on the already increased risk of stroke of such women. In particular, women with migraine who used oral contraceptives were shown to have a 17-fold higher risk of stroke, compared to women without these risk factors. The risk of stroke increased with increasing doses of estrogen intake. Additionally, women with migraines who smoked and used oral contraceptives had an almost 35-fold higher risk of stroke, compared to women with none of these risk factors. The authors emphasize that the finding of a 35-fold increased risk of stroke in migrainous women who smoke and take oral contraceptives is of concern, due to the high prevalence of smoking among women who take the pill. The risks of treatment should be discussed when prescribing oral contraceptives to women with migraines.
Case-control study of migraine and risk of ischaemic stroke in young women.
Tzourio C, Tehindrazanarivelo A, Iglesias S, Alperovitch A, Chedru F, et al.
BMJ 1995;310:830-833 (1 April).The results of this study show that women who use oral contraceptives have a 3-fold increased risk of ischemic stroke, compared to nonusers. The risk increases with increasing doses of estrogen intake. In addition, an increased risk of stroke was observed in women who suffer from migraine. In particular, the presence of migraine without aura was associated with a 3-fold higher risk of stroke, and that of migraines with aura with a 6-fold higher risk of stroke. The concomitant presence of migraines and oral contraceptives use was associated with a 14-fold higher risk of stroke, indicating a multiplication of adverse effects in women with both risk factors.
Cerebrovascular deaths before and after the appearance of oral contraceptives.
Lidegaard O.
Acta Neurol Scand 1987 Jun;75(6):427-33.The results of this study show that in Denmark, rates of cerebrovascular mortality in women increased by 20% since introduction of oral contraceptives, while remained unchanged in men. Deaths from cerebral thromboembolic attacks (CTAs) increased by 33% in women, and decreased by 14% in men, and this increase occurred mostly in women of fertile age in whom use of oral contraceptives is high. The authors conclude that while no factors other than oral contraceptives could be identified to explain this increase, the 3- to 4-fold increased risk of CTAs observed in women using the pill could account for the trend in cerebrovascular mortality observed in women since introduction of oral contraceptives.
Risk of venous thrombosis with use of current low-dose oral contraceptives is not explained by diagnostic suspicion and referral bias.
Bloemenkamp KW, et al.
Arch Intern Med 1999 Jan 11;159(1):65-70.The results of this study show that women using oral contraceptives have a 4- to 5-fold increased risk of developing deep venous thrombosis and pulmonary embolism, compared to nonusers.
Third-generation oral contraceptive and deep venous thrombosis: from epidemiologic controversy to new insight in coagulation.
Vandenbroucke JP; Helmerhorst FM; Bloemenkamp KW; Rosendaal FR.
Am J Obstet Gynecol, 177(4):887-91 1997 Oct.This article reports on four epidemiological studies showing a two-fold increased risk of deep venous thrombosis in women using third generation oral contraceptives (OCs), compared to those using second generation OCs. This effect seems associated to the development of resistance to the blood's own anticoagulation system observed in users of third generation OCs.
Risk of venous thromboembolism with third-generation oral contraceptives: A review.
Weiss G.
Am J Obstet Gynecol, 180(2 Pt 2):295-301 1999 Feb.This review highlights that users of third generation oral contraceptives containing the new progestins desogestrel, gestodene, and norgestimate, have a 2- to 5-fold increased incidence of deep venous thrombosis and pulmonary embolism, compared to users of the older, second generation oral contraceptives. The mechanism underlying the increase in blood clot formation is thought to be the acquisition of resistance to the blood's own anticoagulation system.
Postmarketing surveillance does not catch all adverse events. Letter.
Paul O'Brien.
BMJ 1996;312:577 (2 March).This letter was written in response to an article wrote by Reijnen and Atsma, of Organon Pharmaceuticals, affirming that the risk of deep venous thrombosis and pulmonary embolism associated with the oral contraceptives Marvelon and Mercilon decreases dramatically after the first months of use. These results came from the analysis of the company's surveillance database containing less than 100 reports of such complications. According to P. O'Brien, author of this letter, such database is not representative of the actual rate of adverse reactions to the pills, which can be conservatively estimated at 5,000. Since the manufacturer's database contains less than 2% of cases of venous thromboembolism, no valid conclusion can be drawn from its data. To further affirm this point, O'Brien presents the results of a multicenter study conducted by the World Health Organization showing that the excess risk of venous thromboembolism is maintained throughout the duration of oral contraceptives use.
Venous thromboembolic disease and combined oral contraceptives
Results of international multicentre case-control study. World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Lancet, 346(8990):1575-82 1995 Dec 16.The results of this study show that women who use oral contraceptives (OCs) have a 3-4-fold increased incidence of deep venous thrombosis and subsequent pulmonary embolism, compared to nonusers. The risk increases in users of oral contraceptives containing progestin of the third- rather than second-generation, and does not seem to be affected by duration of treatment.
Effect of different progestagens in low oestrogen oral contraceptives on venous thromboembolic disease.
World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.
Lancet, 346(8990):1582-8 1995 Dec 16.The results of this study show that users of oral contraceptives containing the second- generation progestin levonorgestrel have a 3.4-fold increased risk of venous thromboembolism, compared to nonusers. Users of oral contraceptive containing the third generation progestins desogestrel or gestodene have a 7- and 10-fold increased risk of venous thromboembolism, respectively, compared to nonusers. These data indicate that the risk of this complication is 2-3 times higher in women taking the new generation of oral contraceptives compared to those taking the older ones.
Higher risk of venous thrombosis during early use of oral contraceptives in women with inherited clotting defects.
Bloemenkamp KW, Rosendaal FR, Helmerhorst FM, Vandenbroucke JP.
Arch Intern Med 2000 Jan 10;160(1):49-52.The results of this study show that the risk of developing venous thrombosis in women taking oral contraceptives (OC) is 3 times higher in the first 6 months of use and 2 times higher in the first year of use, than in the following years of use. Women with inherited blood clotting defects have a 19-fold and 11-fold increased risk of deep venous thrombosis during the first 6 months and first year of OC use, respectively. Eighty-three percent of women who developed venous thrombosis in the first year had inherited blood-clotting defects. The authors concluded that the occurrence of this complication in OC users should give the diagnostic suspicion of the presence of a blood-clotting defect.
Enhancement by factor V Leiden mutation of risk of deep-vein thrombosis associated with oral contraceptives containing a third-generation progestagen
Bloemenkamp KW, et al.
Lancet, 346(8990):1593-6 1995 Dec 16.The results of this study show that women employing the newest form of low-dose oral contraceptives containing third generation progestins are at significantly higher risk of developing deep venous thrombosis, compared to users of second and first generation contraceptives. In particular, women taking pills containing the progestin desogestrel (the only third generation progestin available in the U.S.) combined to low dose (30 micrograms) ethinyloestradiol, had a 9-fold increased risk of deep venous thrombosis, compared to nonusers. Women with inherited blood clotting defects (with mutation in the gene coding for the blood clotting factor V -factor V Leiden mutation) who took desogestrel-containing pills had an almost 50-fold increased risk of deep venous thrombosis, compared to women with neither risk factor.
Ethnic distribution of factor V Leiden in 4047 men and women. Implications for venous thromboembolism screening.
Ridker PM, Miletich JP, Hennekens CH, Buring JE.
JAMA, 277(16):1305-7 1997 Apr 23-30.The results of this study show that mutations of the gene coding for coagulation blood factor V -factor V Leiden- are present in 5.3% of Caucasian Americans, 2.2% of Hispanic Americans, 1.2% of African Americans, 1.25% of Native Americans, and 0.45% of Asian Americans. The high prevalence of this mutation among Caucasian Americans might be an important factor when considering initiation of use of oral contraceptives.
Third generation oral contraceptives and risk of venous thromboembolic disorders: an international case-control study.
Transnational Research Group on Oral Contraceptives and the Health of Young Women.
Spitzer WO, Lewis MA, Heinemann LA, Thorogood M, MacRae KD.
BMJ, 312(7023):83-8 1996 Jan 13.The results of this study show that the risk of death from venous thromboembolism in women taking third generation oral contraceptives (OCs) is about 20 per million users per year. In women using second generation OCs the risk of death from this complication is about 14 per million users per year, and in non-users it is five per million per year. These data indicate that use of third generation pills is associated with a 4-fold higher risk of death from venous thromboembolism, compared to nonuse.
Case-control study of risk of cerebral sinus thrombosis in oral contraceptive users who are carriers of hereditary prothrombotic conditions.
The Cerebral Venous Sinus Thrombosis Study Group.
de Bruijn SF, Stam J, Koopman MM, Vandenbroucke JP.
BMJ, 316(7131):589-92 1998 Feb 21.The results of this study show that women who use oral contraceptives (OCs) have a 13-fold increased risk of developing cerebral sinus thrombosis, a complication associated with serious disability of the nervous system, compared to nonusers. The risk of this complication increases by 30-times in women with an inherited prothrombotic condition who use Ocs, compared to those with neither risk factor.
High risk of cerebral-vein thrombosis in carriers of a prothrombin-gene mutation and in users of oral contraceptives.
Martinelli I, Sacchi E, Landi G, Taioli E, Duca F, Mannucci PM.
N Engl J Med, 338(25):1793-7 1998 Jun 18.The results of this study show that use of oral contraceptives (OCs) is associated with a 22-fold increased risk of cerebral sinus thrombosis and a 4.4-fold increased risk of deep venous thrombosis, compared to nonuse. The risk of cerebral sinus thrombosis increases by 150 times in women with inherited clotting defect consisting of a mutation in the protrombin gene.
Coeliac axis thrombosis associated with the combined oral contraceptive pill: a rare cause of an acute abdomen.
Arul GS, Dolan G, Rance CH, Singh SJ, Sommers J.
Pediatr Surg Int, 13(4):285-7 1998 Apr.This article reports on the case of a 14-year-old girl with no risk factors for thromboembolism, who developed thrombosis of the celiac axis and infarction of the spleen 3 weeks after initiation of oral contraceptive use.
Portal vein thrombosis in a 17-year-old female adolescent with essential thrombocytosis.
Mossier C, Kerbl R, Wagner T, Muntean W, Sorantin E, Urban CE.
Pediatr Hematol Oncol, 14(5):457-62 1997 Sep-Oct.This article reports on the case of a 17-year-old girl with essential thrombocytosis who developed portal and hepatic vein thrombosis after initiation of oral contraceptive use.
Prospective study of oral contraceptives and hypertension among women in the United States.
Chasan-Taber L, et al.
Circulation 1996 Aug 1;94(3):483-9.
The results of this study, conducted on over 68,000 women aged 25 to 42 years, show that current users of oral contraceptives have an 80% increased risk of developing hypertension, compared to nonusers. Past use of oral contraceptives is associated with a 20% increased risk of hypertension. Overall, the authors estimated that oral contraceptives cause 41.4 cases of hypertension per 10,000 person-years.
Blood pressure in women using oral contraceptives
Results from the Health Survey for England 1994.
Dong W, Colhoun HM, Poulter NR.
J Hypertens 1997 Oct;15(10):1063-8.The results of this study show that women who use oral contraceptives have significantly higher blood pressure values, compared to nonusers. The difference in blood pressure between users and nonusers persisted even after the results were adjusted for several possible confounders.
Oral contraceptives and breast cancer risk among younger women.
Brinton LA, et al.
J Natl Cancer Inst 1995 Jun 7;87(11):827-35.The results of this study indicate that oral contraceptives increase the risk of breast cancer by 30% in women younger than 45 years, and by 70% in those younger than 35 years. Furthermore, the risk of breast cancer increases by twofold in women who take oral contraceptives for longer than 10 years, and by threefold in women who start taking them early (before the age of 18) and continue to take them for longer than 10 years. The association between oral contraceptives and breast cancer was strongest for the most aggressive type of breast cancers.
Oral contraceptive use at a young age and the risk of breast cancer
An Icelandic, population-based cohort study of the effect of birth year.
Tryggvadottir L, Tulinius H, Gudmundsdottir GB.
Br J Cancer 1997;75(1):139-43.The results of this study show that women who start using oral contraceptives before the age of 20 and continue to use them for at least 4 years, have twice the risk of developing breast cancer, compared to nonusers. The risk increases with increasing duration of oral contraceptive use.
Case-control study of oral contraceptive use and risk of breast cancer.
Rosenberg L, et al.
Am J Epidemiol 1996 Jan 1;143(1):25-37.The results of this study show that women aged 25-34 years who take oral contraceptives for one year or longer have a 70% increased risk of breast cancer, compared to those with shorter duration of use.
Oral contraceptives and breast cancer. Review and meta-analysis.
Romieu I, Berlin JA, Colditz G.
Cancer 1990 Dec 1;66(11):2253-63.This study reviewed the published literature to determine the effects of oral contraceptive use on the incidence of breast cancer. The results of the analysis revealed that women who used oral contraceptives for more than 4 years before their first term pregnancy had a 70% increased risk of breast cancer, compared to nonusers.
Breast cancer and specific types of combined oral contraceptives.
The WHO Collaborative Study of Neoplasia and Steroid Contraceptives.
Thomas DB, Noonan EA.
Br J Cancer, 65(1):108-13 1992 Jan.The results of this study show that users of oral contraceptives have a higher risk of developing breast cancer, compared to nonusers. The risk declines after discontinuation of oral contraceptive use.
Oral contraceptives and invasive adenocarcinomas and adenosquamous carcinomas of the uterine cervix
The World Health Organization Collaborative Study of Neoplasia and Steroid Contraceptives.
Thomas DB; Ray RM.
Am J Epidemiol, 144(3):281-9 1996 Aug 1.The results of this study show that women using oral contraceptives have an increased risk of developing invasive cancer of the uterine cervix, compared to nonusers. The risk increases with increased duration of use. The association between oral contraceptive use and cancer of the uterine cervix is particularly strong in women younger than 35 years.
Oral contraceptive use and risk of invasive cervical cancer.
Brinton LA et al.
Int J Epidemiol, 19(1):4-11 1990 Mar.The results of this study show that women taking oral contraceptives have a 2.2-fold increased risk of developing cancer of the uterine cervix of the adenocarcinoma type, compared to nonusers.
A pooled analysis of case-control studies of thyroid cancer. III. Oral contraceptives, menopausal replacement therapy and other female hormones.
La Vecchia C, et al.
Cancer Causes Control 1999 Apr;10(2):157-66.This study investigated the effects of exogenous female hormones on thyroid cancer risk by analyzing 13 previous studies conducted on a total of 2,132 cases and 3,301 controls. Current use of oral contraceptives was associated with a 50% increased risk of thyroid cancer, and use of fertility drugs and lactation suppression drugs was associated with 60% and 50% increased risk of thyroid cancer, respectively.
Relative risk of liver cancer remains high. Letter.
Horowitz J.
BMJ 1999;319:386 ( 7 August ).This letter emphasizes that the authors of a study conducted by Beral and collegues and published in the British Medical Journal, failed to mention in the text of their article, the finding of a 5-fold increased incidence of liver cancer among users of oral contraceptives, compared to nonusers. Of note, the elevation in risk persisted until at least 10 years after discontinuation of oral contraceptive use.
Cancer of the liver and the use of oral contraceptives.
Forman D, Vincent TJ, Doll R.
Br Med J (Clin Res Ed) 1986 May 24;292(6532):1357-61.The results of this study show that women aged 20-44 years taking oral contraceptives have a four-fold increased risk of dying from liver cancer, compared to nonusers. The risk of dying from liver cancer increases by 20 times in women with a history of use of oral contraceptives of 8 years and longer.
Oral contraceptive use and liver cancer.
Palmer JR, Rosenberg L, Kaufman DW, Warshauer ME, Stolley P, Shapiro S.
Am J Epidemiol 1989 Nov;130(5):878-82.The results of this case-control study confirm previous findings indicating that use of oral contraceptives is associated with an increased risk of liver cancer. In particular, eight of nine (89%) women with hepatocellular carcinoma reported use of oral contraceptives, a percentage significantly higher than that found in matched controls (36%).
Modern oral contraceptive use and benign liver tumors
The German Benign Liver Tumor Case-Control Study.
Heinemann LA, Weimann A, Gerken G, Thiel C, Schlaud M, DoMinh T.
Eur J Contracept Reprod Health Care 1998 Dec;3(4):194-200.The results of this study show that users of oral contraceptives have a 25% increased risk of developing liver adenomas and a twofold increased risk of developing liver focal nodular hyperplasia, compared to nonusers.
Oral contraceptive use and risk of gestational trophoblastic tumors.
Palmer JR, et al.
J Natl Cancer Inst 1999 Apr 7;91(7):635-40.The results of this study show that use of oral contraceptives is associated with a twofold increased incidence of gestational trophoblastic tumors, compared to nonuse. The risk increases by 4-folds in women who become pregnant while taking oral contraceptives.
Oral contraceptives and other risk factors for gallbladder disease.
Strom BL, et al.
Clin Pharmacol Ther 1986 Mar;39(3):335-41.The results of this study, conducted on approximately 480,000 women, show that those aged 15 to 19 years taking oral contraceptives have a three-fold increased risk of symptomatic gall bladder disease requiring medical treatment, compared to nonusers. The risk decreases with increasing age of use, down to a 20% higher risk in women aged 40-44 years.
A prospective study of symptomatic gallstones in women: relation with oral contraceptives and other risk factors.
Grodstein F, Colditz GA, Hunter DJ, Manson JE, Willett WC, Stampfer MJ.
Obstet Gynecol 1994 Aug;84(2):207-14.The results of this study show that use of oral contraceptives (OCs) is associated with an overall 20% increased risk of gall bladder disease requiring medical treatment. Current users of oral contraceptives have a 60% increased risk of symptomatic gall bladder disease. The risk increases with increasing duration of treatment, and is 50% higher in women who took OCs for 10-14 years and 60% higher in those who took them for 15 or more years, compared to nonusers.
Biliary disease in young women and its association with pregnancy or oral contraceptives.
Evron S, Frankel M, Diamant Y.
Int Surg 1982 Oct-Dec;67(4 Suppl):448-50.The results of this study indicate that the increase in use of oral contraceptives observed in women aged 22-28 during the years 1967-1976, has been responsible for the over twofold increase in rate of gall bladder removal recorded in those years.
Oral contraceptives in systemic lupus erythematosus: side-effects and influence on the activity of SLE.
Julkunen HA.
Scand J Rheumatol, 20(6):427-33 1991.The results of this study indicate that women with systemic lupus erythematosus who use oral contraceptives are at higher risk of developing complications such as activation and exacerbation of lupus, kidney involvement, deep venous thrombosis and gynecological disturbances, compared to nonusers. Since the risk of disease activation and kidney disease was observed especially in users of oral contraceptives containing a combination of estrogen and progestin, the author concludes that it is best to avoid use of this type of pill in women with high level of disease activity or with active nephritis.
Increased risk of inflammatory bowel disease associated with oral contraceptive use.
Boyko EJ, Theis MK, Vaughan TL, Nicol-Blades B.
Am J Epidemiol 1994 Aug 1;140(3):268-78.The results of this study show that the risk of developing ulcerative colitis and Crohn's disease increases by 2- and 2.6-folds, respectively, in women who used oral contraceptives in the 6 months prior the onset of the disease, compared to nonusers. The risk of Crohn's disease, but not that of ulcerative colitis, increases with increasing duration of oral contraceptive use, and women who took the pill for more than 6 years were shown to have a 5-fold increased risk of developing the disease, compared to nonusers.
Evidence for an increased risk of Crohn's disease in oral contraceptive users.
Lesko SM, et al.
Gastroenterology 1985 Nov;89(5):1046-9.The results of this study show that the risk of Crohn's disease increases by twofold in women who use oral contraceptives, compared to nonusers. Women who used oral contraceptives in the year before the onset of the disease had an over 4-fold increased risk of Crohn's disease, and those who took them for 5 or more years before the onset of disease had a 8-fold increased risk, compared to nonusers.
Oral contraceptive use and the risk of inflammatory bowel disease.
Sandler RS, Wurzelmann JI, Lyles CM.
Epidemiology 1992 Jul;3(4):374-8.The results of this study show that oral contraceptive use is associated with a 50% increased risk Crohn's disease. The combination of oral contraceptive use and smoking increases the risk of Crohn's disease by 2.6-folds.
A prospective study of oral contraceptives and NIDDM among U.S. women.
Chasan-Taber L, et al.
Diabetes Care 1997 Mar;20(3):330-5.The results of this study, conducted on over 98,000 women aged 25-42 and followed up for 4 years, show that users of oral contraceptives have a 60% increased risk of developing type 2 diabetes, compared to nonusers. After adjusting for several confounders, use of oral contraceptives was found to be associated with a 30% increased risk of diabetes.
