"If you do not want to get pregnant, there are many birth control options to choose from. No one product is best for everyone. The only sure way to avoid pregnancy and sexually transmitted infections (STIs or STDs) is not to have any sexual"...
Cigarette smoking increases the risk of serious cardiovascular side effects from oral contraceptive use. This risk increases with age and with heavy smoking (15 or more cigarettes per day) and is quite marked in women over 35 years of age. Women who use oral contraceptives should be strongly advised not to smoke.
The use of oral contraceptives is associated with increased risks of several serious conditions including myocardial infarction, thromboembolism, stroke, hepatic neoplasia, and gallbladder disease, although the risk of serious morbidity or mortality is very small in healthy women without underlying risk factors. The risk of morbidity and mortality increases significantly in the presence of other underlying risk factors such as hypertension, hyperlipidemias, obesity, and diabetes.
Practitioners prescribing oral contraceptives should be familiar with the following information relating to these risks.
The information contained in this package insert is principally based on studies carried out in patients who used oral contraceptives with formulations of higher doses of estrogens and progestogens than those in common use today. The effect of long-term use of the oral contraceptives with formulations of lower doses of both estrogens and progestogens remains to be determined.
Throughout this labeling, epidemiologic studies reported are of two types: retrospective or case control studies and prospective or cohort studies. Case control studies provide a measure of the relative risk of a disease, namely, a ratio of the incidence of a disease among oral contraceptive users to that among non-users. The relative risk does not provide information on the actual clinical occurrence of a disease. Cohort studies provide a measure of attributable risk, which is the difference in the incidence of disease between oral contraceptive users and non-users. The attributable risk does provide information about the actual occurrence of a disease in the population (Adapted from refs. 2 and 3 with the authors' permission). For further information, the reader is referred to a text on epidemiologic methods.
Thromboembolic Disorders And Other Vascular Problems
An increased risk of thromboembolic and thrombotic disease associated with the use of oral contraceptives is well established. Case control studies have found the relative risk of users compared to nonusers to be 3 for the first episode of superficial venous thromboembolic disease, 4 to 11 for deep vein thrombosis or pulmonary embolism, and 1.5 to 6 for women with predisposing conditions for venous thromboembolic disease (2,3,19-24). Cohort studies have shown the relative risk to be somewhat lower, about 3 for new cases and about 4.5 for new cases requiring hospitalization (25). The risk of thromboembolic disease associated with oral contraceptives is not related to length of use and disappears after pill use is stopped (2).
Several epidemiologic studies indicate that third generation oral contraceptives, including those containing desogestrel, are associated with a higher risk of venous thromboembolism than certain second generation oral contraceptives (102-104). In general, these studies indicate an approximate two-fold increased risk, which corresponds to an additional 1-2 cases of venous thromboembolism per 10,000 women-years of use. However, data from additional studies have not shown this two-fold increase in risk.
A two- to four-fold increase in relative risk of post-operative thromboembolic complications has been reported with the use of oral contraceptives (9, 26). The relative risk of venous thrombosis in women who have predisposing conditions is twice that of women without such medical conditions (9, 26). If feasible, oral contraceptives should be discontinued at least four weeks prior to and for two weeks after elective surgery of a type associated with an increase in risk of thromboembolism and during and following prolonged immobilization. Since the immediate postpartum period is associated with an increased risk of thromboembolism, oral contraceptives should be started no earlier than four weeks after delivery in women who elect not to breast feed.
An increased risk of myocardial infarction has been attributed to oral contraceptive use. This risk is primarily in smokers or women with other underlying risk factors for coronary artery disease such as hypertension, hypercholesterolemia, morbid obesity, and diabetes. The relative risk of heart attack for current oral contraceptive users has been estimated to be two to six (4-10). The risk is very low in women under the age of 30.
Smoking in combination with oral contraceptive use has been shown to contribute substantially to the incidence of myocardial infarction in women in their mid-thirties or older with smoking accounting for the majority of excess cases (11). Mortality rates associated with circulatory disease have been shown to increase substantially in smokers, over the age of 35 and non-smokers over the age of 40 (Table III) among women who use oral contraceptives.
TABLE III: CIRCULATORY DISEASE MORTALITY RATES PER
100,000 WOMAN-YEARS BY AGE, SMOKING STATUS, AND ORAL CONTRACEPTIVE USE
Adapted from P.M. Layde and V. Beral, ref. #12.
Oral contraceptives may compound the effects of well-known risk factors, such as hypertension, diabetes, hyperlipidemias, age and obesity (13). In particular, some progestogens are known to decrease HDL cholesterol and cause glucose intolerance, while estrogens may create a state of hyperinsulinism (14-18). Oral contraceptives have been shown to increase blood pressure among users (see section 9 in WARNINGS). Similar effects on risk factors have been associated with an increased risk of heart disease. Oral contraceptives must be used with caution in women with cardiovascular disease risk factors.
Oral contraceptives have been shown to increase both the relative and attributable risks of cerebrovascular events (thrombotic and hemorrhagic strokes), although, in general, the risk is greatest among older ( > 35 years), hypertensive women who also smoke. Hypertension was found to be a risk factor for both users and non-users, for both types of strokes, while smoking interacted to increase the risk for hemorrhagic strokes (27-29).
In a large study, the relative risk of thrombotic strokes has been shown to range from 3 for normotensive users to 14 for users with severe hypertension (30). The relative risk of hemorrhagic stroke is reported to be 1.2 for non-smokers who used oral contraceptives, 2.6 for smokers who did not use oral contraceptives, 7.6 for smokers who used oral contraceptives, 1.8 for normotensive users and 25.7 for users with severe hypertension (30). The attributable risk is also greater in older women (3).
Dose-related risk of vascular disease from oral contraceptives
A positive association has been observed between the amount of estrogen and progestogen in oral contraceptives and the risk of vascular disease (31-33). A decline in serum high-density lipoproteins (HDL) has been reported with many progestational agents (14-16). A decline in serum high-density lipoproteins has been associated with an increased incidence of ischemic heart disease. Because estrogens increase HDL cholesterol, the net effect of an oral contraceptive depends on a balance achieved between doses of estrogen and progestogen and the nature and absolute amount of progestogens used in the contraceptives. The amount of both hormones should be considered in the choice of an oral contraceptive.
Minimizing exposure to estrogen and progestogen is in keeping with good principles of therapeutics. For any particular estrogen/progestogen combination, the dosage regimen prescribed should be one which contains the least amount of estrogen and progestogen that is compatible with a low failure rate and the needs of the individual patient. New acceptors of oral contraceptive agents should be started on preparations containing 0.035 mg or less of estrogen.
Persistence of risk of vascular disease
There are two studies which have shown persistence of risk of vascular disease for ever-users of oral contraceptives. In a study in the United States, the risk of developing myocardial infarction after discontinuing oral contraceptives persists for at least 9 years for women 40-49 years old who had used oral contraceptives for five or more years, but this increased risk was not demonstrated in other age groups (8). In another study in Great Britain, the risk of developing cerebrovascular disease persisted for at least 6 years after discontinuation of oral contraceptives, although excess risk was very small (34). However, both studies were performed with oral contraceptive formulations containing 50 micrograms or more of estrogen.
Estimates Of Mortality From Contraceptive Use
One study gathered data from a variety of sources which have estimated the mortality rate associated with different methods of contraception at different ages (Table IV). These estimates include the combined risk of death associated with contraceptive methods plus the risk attributable to pregnancy in the event of method failure. Each method of contraception has its specific benefits and risks. The study concluded that with the exception of oral contraceptive users 35 and older who smoke and 40 and older who do not smoke, mortality associated with all methods of birth control is low and below that associated with childbirth.
The observation of a possible increase in risk of mortality with age for oral contraceptive users is based on data gathered in the 1970's - but not reported until 1983 (35). However, current clinical practice involves the use of lower estrogen formulations combined with careful consideration of risk factors.
Because of these changes in practice and, also, because of some limited new data which suggest that the risk of cardiovascular disease with the use of oral contraceptives may now be less than previously observed (100,101), the Fertility and Maternal Health Drugs Advisory Committee was asked to review the topic in 1989. The Committee concluded that although cardiovascular disease risks may be increased with oral contraceptive use after age 40 in healthy non-smoking women (even with the newer low-dose formulations), there are also greater potential health risks associated with pregnancy in older women and with the alternative surgical and medical procedures which may be necessary if such women do not have access to effective and acceptable means of contraception.
Therefore, the Committee recommended that the benefits of low-dose oral contraceptive use by healthy non-smoking women over 40 may outweigh the possible risks. Of course, older women, as all women who take oral contraceptives, should take the lowest possible dose formulation that is effective.
TABLE IV: ANNUAL NUMBER OF BIRTH-RELATED OR
METHOD-RELATED DEATHS ASSOCIATED WITH CONTROL OF FERTILITY PER 100,000
NON-STERILE WOMEN, BY FERTILITY CONTROL METHOD ACCORDING TO AGE
|Method of control and outcome||15-19||20-24||25-29||30-34||35-39||40-44|
|No fertility control methodsa||7||7.4||9.1||14.8||25.7||28.2|
|Oral contraceptives non-smokerb||0.3||0.5||0.9||1.9||13.8||31.6|
|Oral contraceptives smokerb||2.2||3.4||6.6||13.5||51.1||117.2|
|a Deaths are birth related
b Deaths are method related
Adapted from H.W. Ory, ref. #35.
Carcinoma Of The Reproductive Organs And Breasts
Numerous epidemiologic studies have been performed on the incidence of breast, endometrial, ovarian, and cervical cancer in women using oral contraceptives. While there are conflicting reports, most studies suggest that the use of oral contraceptives is not associated with an overall increase in the risk of developing breast cancer. Some studies have reported an increased relative risk of developing breast cancer, particularly at a younger age. This increased relative risk appears to be related to duration of use (36-43, 79-89).
Some studies suggest that oral contraceptive use has been associated with an increase in the risk of cervical intra-epithelial neoplasia in some populations of women (45-48). However, there continues to be controversy about the extent to which such findings may be due to differences in sexual behavior and other factors.
Benign hepatic adenomas are associated with oral contraceptive use, although the incidence of benign tumors is rare in the United States. Indirect calculations have estimated the attributable risk to be in the range of 3.3 cases/100,000 for users, a risk that increases after four or more years of use especially with oral contraceptives of higher dose (49). Rupture of rare, benign, hepatic adenomas may cause death through intra-abdominal hemorrhage (50, 51).
Studies from Britain have shown an increased risk of developing hepatocellular carcinoma (52-54) in long-term ( > 8 years) oral contraceptive users. However, these cancers are extremely rare in the US and the attributable risk (the excess incidence) of liver cancers in oral contraceptive users approaches less than one per million users.
There have been clinical case reports of retinal thrombosis associated with the use of oral contraceptives. Oral contraceptives should be discontinued if there is unexplained partial or complete loss of vision; onset of proptosis or diplopia; papilledema; or retinal vascular lesions. Appropriate diagnostic and therapeutic measures should be undertaken immediately.
Oral Contraceptive Use Before Or During Early Pregnancy
Extensive epidemiologic studies have revealed no increased risk of birth defects in women who have used oral contraceptives prior to pregnancy (55-57). Studies also do not suggest a teratogenic effect, particularly in so far as cardiac anomalies and limb reduction defects are concerned (55,56,58,59), when oral contraceptives are taken inadvertently during early pregnancy.
The administration of oral contraceptives to induce withdrawal bleeding should not be used as a test for pregnancy. Oral contraceptives should not be used during pregnancy to treat threatened or habitual abortion. It is recommended that for any patient who has missed two consecutive periods, pregnancy should be ruled out before continuing oral contraceptive use. If the patient has not adhered to the prescribed schedule, the possibility of pregnancy should be considered at the first missed period. Oral contraceptive use should be discontinued until pregnancy is ruled out.
Earlier studies have reported an increased lifetime relative risk of gallbladder surgery in users of oral contraceptives and estrogens (60, 61). More recent studies, however, have shown that the relative risk of developing gallbladder disease among oral contraceptive users may be minimal (62-64). The recent findings of minimal risk may be related to the use of oral contraceptive formulations containing lower hormonal doses of estrogens and progestogens.
Carbohydrate And Lipid Metabolic Effects
Oral contraceptives have been shown to cause a decrease in glucose tolerance in a significant percentage of users (17). Oral contraceptives containing greater than 75 micrograms of estrogens cause hyper-insulinism, while lower doses of estrogen cause less glucose intolerance (65). Progestogens increase insulin secretion and create insulin resistance, this effect varying with different progestational agents (17, 66). However, in the non-diabetic woman, oral contraceptives appear to have no effect on fasting blood glucose (67). Because of these demonstrated effects, prediabetic and diabetic women should be carefully monitored while taking oral contraceptives.
A small proportion of women will have persistent hypertriglyceridemia while on the pill. As discussed earlier (see WARNINGS), changes in serum triglycerides and lipoprotein levels have been reported in oral contraceptive users.
Elevated Blood Pressure
An increase in blood pressure has been reported in women taking oral contraceptives (68) and this increase is more likely in older oral contraceptive users (69) and with continued use (61). Data from the Royal College of General Practitioners (12) and subsequent randomized trials have shown that the incidence of hypertension increases with increasing quantities of progestogens.
Women with a history of hypertension or hypertension-related diseases, or renal disease (70) should be encouraged to use another method of contraception. If women elect to use oral contraceptives, they should be monitored closely and if significant elevation of blood pressure occurs, oral contraceptives should be discontinued. For most women, elevated blood pressure will return to normal after stopping oral contraceptives (69), and there is no difference in the occurrence of hypertension between ever- and never-users (68,70,71).
The onset or exacerbation of migraine or development of headache with a new pattern which is recurrent, persistent, or severe requires discontinuation of oral contraceptives and evaluation of the cause.
Breakthrough bleeding and spotting are sometimes encountered in patients on oral contraceptives, especially during the first three months of use. Non-hormonal causes should be considered and adequate diagnostic measures taken to rule out malignancy or pregnancy in the event of breakthrough bleeding, as in the case of any abnormal vaginal bleeding. If pathology has been excluded, time or a change to another formulation may solve the problem. In the event of amenorrhea, pregnancy should be ruled out.
Some women may encounter post-pill amenorrhea or oligomenorrhea, especially when such a condition was pre-existent.
Patients should be counseled that this product does not protect against HIV infection (AIDS) and other sexually transmitted diseases.
Physical Examination And Follow Up
It is good medical practice for all women to have annual history and physical examinations, including women using oral contraceptives. The physical examination, however, may be deferred until after initiation of oral contraceptives if requested by the woman and judged appropriate by the clinician. The physical examination should include special reference to blood pressure, breasts, abdomen, and pelvic organs, including cervical cytology, and relevant laboratory tests. In case of undiagnosed, persistent or recurrent abnormal vaginal bleeding, appropriate measures should be conducted to rule out malignancy. Women with a strong family history of breast cancer or who have breast nodules should be monitored with particular care.
Women who are being treated for hyperlipidemias should be followed closely if they elect to use oral contraceptives. Some progestogens may elevate LDL levels and may render the control of hyperlipidemias more difficult.
Oral contraceptives may cause some degree of fluid retention. They should be prescribed with caution, and only with careful monitoring, in patients with conditions which might be aggravated by fluid retention.
Women with a history of depression should be carefully observed and the drug discontinued if depression recurs to a serious degree.
See WARNINGS section.
Pregnancy Category X (see CONTRAINDICATIONS and WARNINGS sections).
Small amounts of oral contraceptive steroids have been identified in the milk of nursing mothers and a few adverse effects on the child have been reported, including jaundice and breast enlargement. In addition, oral contraceptives given in the postpartum period may interfere with lactation by decreasing the quantity and quality of breast milk. If possible, the nursing mother should be advised not to use oral contraceptives but to use other forms of contraception until she has completely weaned her child.
Safety and efficacy of VIORELE has been established in women of reproductive age. Safety and efficacy are expected to be the same for post-pubertal adolescents under the age of 16 and for users 16 years and older. Use of this product before menarche is not indicated.
Information For The Patient
See Patient Labeling.
2. Stadel BV. Oral contraceptives and cardiovascular disease. (Pt. 1). N Engl J Med 1981; 305:612-618.
3. Stadel BV. Oral contraceptives and cardiovascular disease. (Pt. 2). N Engl J Med 1981; 305:672-677.
4. Adam SA, Thorogood M. Oral contraception and myocardial infarction revisited: the effects of new preparations and prescribing patterns. Br J Obstet and Gynecol 1981; 88:838-845.
5. Mann JI, Inman WH. Oral contraceptives and death from myocardial infarction. Br Med J 1975; 2(5965):245-248.
6. Mann JI, Vessey MP, Thorogood M, Doll R. Myocardial infarction in young women with special reference to oral contraceptive practice. Br Med J 1975; 2(5956):241-245.
7. Royal College of General Practitioners' Oral Contraception Study: Further analyses of mortality in oral contraceptive users. Lancet 1981; 1:541-546.
8. Slone D, Shapiro S, Kaufman DW, Rosenberg L, Miettinen OS, Stolley PD. Risk of myocardial infarction in relation to current and discontinued use of oral contraceptives. N Engl J Med 1981; 305:420-424.
9. Vessey MP. Female hormones and vascular disease-an epidemiological overview. Br J Fam Plann 1980; 6:1-12.
10. Russell-Briefel RG, Ezzati TM, Fulwood R, Perlman JA, Murphy RS. Cardiovascular risk status and oral contraceptive use, United States, 1976-80. Prevent Med 1986; 15:352-362.
11. Goldbaum GM, Kendrick JS, Hogelin GC, Gentry EM. The relative impact of smoking and oral contraceptive use on women in the United States. JAMA 1987; 258:1339-1342.
12. Layde PM, Beral V. Further analyses of mortality in oral contraceptive users: Royal College General Practitioners' Oral Contraception Study. (Table 5) Lancet 1981; 1:541-546.
13. Knopp RH. Arteriosclerosis risk: the roles of oral contraceptives and postmenopausal estrogens. J Reprod Med 1986; 31(9) (Supplement):913-921.
14. Krauss RM, Roy S, Mishell DR, Casagrande J, Pike MC. Effects of two low-dose oral contraceptives on serum lipids and lipoproteins: Differential changes in high-density lipoproteins subclasses. Am J Obstet 1983; 145:446-452.
15. Wahl P, Walden C, Knopp R, Hoover J, Wallace R, Heiss G, Rifkind B. Effect of estrogen/progestin potency on lipid/lipoprotein cholesterol. N Engl J Med 1983; 308:862-867.
16. Wynn V, Niththyananthan R. The effect of progestin in combined oral contraceptives on serum lipids with special reference to high-density lipoproteins. Am J Obstet Gynecol 1982; 142:766-771.
17. Wynn V, Godsland I. Effects of oral contraceptives and carbohydrate metabolism. J Reprod Med 1986; 31 (9) (Supplement):892-897.
18. LaRosa JC. Atherosclerotic risk factors in cardiovascular disease. J Reprod Med 1986; 31 (9) (Supplement):906-912.
19. Inman WH, Vessey MP. Investigation of death from pulmonary, coronary, and cerebral thrombosis and embolism in women of child-bearing age. Br Med J 1968; 2 (5599):193-199.
20. Maguire MG, Tonascia J, Sartwell PE, Stolley PD, Tockman MS. Increased risk of thrombosis due to oral contraceptives: a further report. Am J Epidemiol 1979; 110 (2):188-195.
21. Pettiti DB, Wingerd J, Pellegrin F, Ramacharan S. Risk of vascular disease in women: smoking, oral contraceptives, noncontraceptive estrogens, and other factors. JAMA 1979; 242:1150-1154.
22. Vessey MP, Doll R. Investigation of relation between use of oral contraceptives and thromboembolic disease. Br Med J 1968; 2 (5599):199-205.
23. Vessey MP, Doll R. Investigation of relation between use of oral contraceptives and thromboembolic disease. A further report. Br Med J 1969; 2 (5658):651-657.
24. Porter JB, Hunter JR, Danielson DA, Jick H, Stergachis A. Oral contraceptives and non-fatal vascular disease-recent experience. Obstet Gynecol 1982; 59 (3):299-302.
25. Vessey M, Doll R, Peto R, Johnson B, Wiggins P. A long-term follow-up study of women using different methods of contraception: an interim report. Biosocial Sci 1976; 8:375-427.
26. Royal College of General Practitioners: Oral contraceptives, venous thrombosis, and varicose veins. J Royal Coll Gen Pract 1978; 28:393-399.
27. Collaborative Group for the Study of Stroke in Young Women: Oral contraception and increased risk of cerebral ischemia or thrombosis. N Engl J Med 1973; 288:871-878.
28. Petitti DB, Wingerd J. Use of oral contraceptives, cigarette smoking, and risk of subarachnoid hemorrhage. Lancet 1978; 2:234-236.
29. Inman WH. Oral contraceptives and fatal sub-arachnoid hemorrhage. Br Med J 1979; 2 (6203):1468-70.
30. Collaborative Group for the Study of Stroke in Young Women: Oral contraceptives and stroke in young women: associated risk factors. JAMA 1975; 231:718-722.
31. Inman WH, Vessey MP, Westerholm B, Engelund A. Thromboembolic disease and the steroidal content of oral contraceptives. A report to the Committee on Safety of Drugs. Br Med J 1970; 2:203-209.
32. Meade TW, Greenberg G, Thompson SG. Progestogens and cardiovascular reactions associated with oral contraceptives and a comparison of the safety of 50- and 35-mcg oestrogen preparations. Br Med J 1980; 280 (6224):1157-1161.
33. Kay CR. Progestogens and arterial disease-evidence from the Royal College of General Practitioners' Study. Am J Obstet Gynecol 1982; 142:762-765.
34. Royal College of General Practitioners: Incidence of arterial disease among oral contraceptive users. J Royal Coll Gen Pract 1983; 33:75-82.
35. Ory HW. Mortality associated with fertility and fertility control: 1983. Family Planning Perspectives 1983; 15:50-56.
36. The Cancer and Steroid Hormone Study of the Centers for Disease Control and the National Institute of Child Health and Human Development: Oral-contraceptive use and the risk of breast cancer. N Engl J Med 1986; 315:405-411.
37. Pike MC, Henderson BE, Krailo MD, Duke A, Roy S. Breast cancer risk in young women and use of oral contraceptives: possible modifying effect of formulation and age at use. Lancet 1983; 2:926-929.
38. Paul C, Skegg DG, Spears GFS, Kaldor JM. Oral contraceptives and breast cancer: A national study. Br Med J 1986; 293:723-725.
39. Miller DR, Rosenberg L, Kaufman DW, Schottenfeld D, Stolley PD, Shapiro S. Breast cancer risk in relation to early oral contraceptive use. Obstet Gynecol 1986; 68:863-868.
40. Olson H, Olson KL, Moller TR, Ranstam J, Holm P. Oral contraceptive use and breast cancer in young women in Sweden (letter). Lancet 1985; 2:748-749.
41. McPherson K, Vessey M, Neil A, Doll R, Jones L, Roberts M. Early contraceptive use and breast cancer: Results of another case-control study. Br J Cancer 1987; 56:653-660.
42. Huggins GR, Zucker PF. Oral contraceptives and neoplasia: 1987 update. Fertil Steril 1987; 47:733-761.
43. McPherson K, Drife JO. The pill and breast cancer: why the uncertainty? Br Med J 1986; 293:709-710.
45. Ory H, Naib Z, Conger SB, Hatcher RA, Tyler CW. Contraceptive choice and prevalence of cervical dysplasia and carcinoma in situ. Am J Obstet Gynecol 1976; 124:573-577.
46. Vessey MP, Lawless M, McPherson K, Yeates D. Neoplasia of the cervix uteri and contraception: a possible adverse effect of the pill. Lancet 1983; 2:930.
47. Brinton LA, Huggins GR, Lehman HF, Malli K, Savitz DA, Trapido E, Rosenthal J, Hoover R. Long-term use of oral contraceptives and risk of invasive cervical cancer. Int J Cancer 1986; 38:339-344.
48. WHO Collaborative Study of Neoplasia and Steroid Contraceptives: Invasive cervical cancer and combined oral contraceptives. Br Med J 1985; 209:961-965.
49. Rooks JB, Ory HW, Ishak KG, Strauss LT, Greenspan JR, Hill AP, Tyler CW. Epidemiology of hepatocellular adenoma: the role of oral contraceptive use. JAMA 1979; 242:644-648.
50. Bein NN, Goldsmith HS. Recurrent massive hemorrhage from benign hepatic tumors secondary to oral contraceptives. Br J Surg 1977; 64:433-435.
51. Klatskin G. Hepatic tumors: possible relationship to use of oral contraceptives. Gastroenterology 1977; 73:386-394.
52. Henderson BE, Preston-Martin S, Edmondson HA, Peters RL, Pike MC. Hepatocellular carcinoma and oral contraceptives. Br J Cancer 1983; 48:437-440.
53. Neuberger J, Forman D, Doll R, Williams R. Oral contraceptives and hepatocellular carcinoma. Br Med J 1986; 292:1355-1357.
54. Forman D, Vincent TJ, Doll R. Cancer of the liver and oral contraceptives. Br Med J 1986; 292:1357-1361.
55. Harlap S, Eldor J. Births following oral contraceptive failures. Obstet Gynecol 1980; 55:447-452.
56. Savolainen E, Saksela E, Saxen L. Teratogenic hazards of oral contraceptives analyzed in a national malformation register. Am J Obstet Gynecol 1981; 140:521-524.
57. Janerich DT, Piper JM, Glebatis DM. Oral contraceptives and birth defects. Am J Epidemiol 1980; 112:73-79.
58. Ferencz C, Matanoski GM, Wilson PD, Rubin JD, Neill CA, Gutberlet R. Maternal hormone therapy and congenital heart disease. Teratology 1980; 21:225-239.
59. Rothman KJ, Fyler DC, Goldbatt A, Kreidberg MB. Exogenous hormones and other drug exposures of children with congenital heart disease. Am J Epidemiol 1979; 109:433-439.
60. Boston Collaborative Drug Surveillance Program: Oral contraceptives and venous thromboembolic disease, surgically confirmed gallbladder disease, and breast tumors. Lancet 1973; 1:1399-1404.
61. Royal College of General Practitioners: Oral contraceptives and health. New York, Pittman, 1974.
62. Layde PM, Vessey MP, Yeates D. Risk of gallbladder disease: a cohort study of young women attending family planning clinics. J Epidemiol Community Health 1982; 36:274-278.
63. Rome Group for the Epidemiology and Prevention of Cholelithiasis (GREPCO): Prevalence of gallstone disease in an Italian adult female population. Am J Epidemiol 1984; 119:796-805.
64. Strom BL, Tamragouri RT, Morse ML, Lazar EL, West SL, Stolley PD, Jones JK. Oral contraceptives and other risk factors for gallbladder disease. Clin Pharmacol Ther 1986; 39:335-341.
65. Wynn V, Adams PW, Godsland IF, Melrose J, Niththyananthan R, Oakley NW, Seedj A. Comparison of effects of different combined oral-contraceptive formulations on carbohydrate and lipid metabolism. Lancet 1979; 1:1045-1049.
66. Wynn V. Effect of progesterone and progestins on carbohydrate metabolism. In Progesterone and Progestin. Edited by Bardin CW, Milgrom E, Mauvis-Jarvis P. New York, Raven Press, 1983 pp. 395-410.
67. Perlman JA, Roussell-Briefel RG, Ezzati TM, Lieberknecht G. Oral glucose tolerance and the potency of oral contraceptive progestogens. J Chronic Dis 1985; 38:857-864.
68. Royal College of General Practitioners' Oral Contraception Study: Effect on hypertension and benign breast disease of progestogen component in combined oral contraceptives. Lancet 1977; 1:624.
69. Fisch IR, Frank J. Oral contraceptives and blood pressure. JAMA 1977; 237:2499-2503.
70. Laragh AJ. Oral contraceptive induced hypertension-nine years later. Am J Obstet Gynecol 1976; 126:141-147.
71. Ramcharan S, Peritz E, Pellegrin FA, Williams WT. Incidence of hypertension in the Walnut Creek Contraceptive Drug Study cohort. In Pharmacology of Steroid Contraceptive Drugs. Garattini S, Berendes HW. Eds. New York, Raven Press, 1977 pp. 277-288. (Monographs of the Mario Negri Institute for Pharmacological Research, Milan).
79. Schlesselman J, Stadel BV, Murray P, Lai S. Breast Cancer in relation to early use of oral contraceptives 1988; 259:1828-1833.
80. Hennekens CH, Speizer FE, Lipnick RJ, Rosner B, Bain C, Belanger C, Stampfer MJ, Willett W, Peto R. A case-controlled study of oral contraceptive use and breast cancer. JNCI 1984; 72:39-42.
81. LaVecchia C, Decarli A, Fasoli M, Franceschi S, Gentile A, Negri E, Parazzini F, Tognoni G. Oral contraceptives and cancers of the breast and of the female genital tract. Interim results from a case-control study. Br. J. Cancer 1986; 54:311-317.
82. Meirik O, Lund E, Adami H, Bergstrom R, Christoffersen T, Bergsjo P. Oral contraceptive use in breast cancer in young women. A Joint National Case-control study in Sweden and Norway. Lancet 1986; 11:650-654.
83. Kay CR, Hannaford PC. Breast cancer and the pill-A further report from the Royal College of General Practitioners' oral contraception study. Br. J. Cancer 1988; 58:675-680.
84. Stadel BV, Lai S, Schlesselman JJ, Murray P. Oral contraceptives and premenopausal breast cancer in nulliparous women. Contraception 1988; 38:287-299.
85. Miller DR, Rosenberg L, Kaufman DW, Stolley P, Warshauer ME, Shapiro S. Breast cancer before age 45 and oral contraceptive use: New Findings. Am. J. Epidemiol 1989; 129:269-280.
86. The UK National Case-Control Study Group, Oral contraceptive use and breast cancer risk in young women. Lancet 1989; 1:973-982.
87. Schlesselman JJ. Cancer of the breast and reproductive tract in relation to use of oral contraceptives. Contraception 1989; 40:1-38.
88. Vessey MP, McPherson K, Villard-Mackintosh L, Yeates D. Oral contraceptives and breast cancer: latest findings in a large cohort study. Br. J. Cancer 1989; 59:613-617.
89. Jick SS, Walker AM, Stergachis A, Jick H. Oral contraceptives and breast cancer. Br. J. Cancer 1989; 59:618-621.
102. Jick H, Jick SS, Gurewich V, Myers MW, Vasilakis C. Risk of idiopathic cardiovascular death and non-fatal venous thromboembolism in women using oral contraceptives with differing progestagen components. Lancet, 1995; 346:1589-93.
103. World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. Effect of different progestagens in low oestrogen oral contraceptives on venous thromboembolic disease. Lancet, 1995; 346:1582-88.
104. Spitzer WO, Lewis MA, Heinemann LAJ, Thorogood M, MacRae KD on behalf of Transnational Research Group on Oral Contraceptives and Health of Young Women. Third generation oral contraceptives and risk of venous thromboembolic disorders: An international case-control study. Br Med J, 1996; 312:83-88.
Last reviewed on RxList: 6/1/2012
This monograph has been modified to include the generic and brand name in many instances.
Additional Viorele Information
Report Problems to the Food and Drug Administration
Find out what women really need.