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 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Current findings and controversies between oral contraceptives (OCs) and cardiovascular disease and cancers. Specifically, venous thromboembolism, stroke, myocardial infarction, (MI), atherosclerosis, breast cancer, cervical cancer, endometrial cancer, and ovarian cancer are reviewed. The concentration in the literature is on higher dose estrogen (at least 50 mg) studies which suggest that there is with current users, particularly older women who smoke, a risk of myocardial infarction, venous thrombosis, and subarachnoid hemorrhage. Of the 11 case control studies and 4 cohort studies it appears that venous thrombosis increases in risk with an increase in estrogen content and remains constant for duration of use. However, definitive studies have not been completed on 50 mg doses of ethinyl estradiol (EE) and mestranol (ME). The actual individual risk may be small, 1/1000 current users/year. Thrombotic and hemorrhagic stroke in the 1970s had a risk of 37/100,000 users per year, mostly among smokers 35 years and older with predisposing medical conditions. It is suggested that although there were mixed findings between current and past users in the 1970s low dose current or past users are not substantially at risk. The pre-mid 1970 risk of MI was 7 and 67 cases/100,000 current users ged 30-39 respectively per year. The risk group is similar to stroke. Thrombosis seems to be responsible for the increased risk, rather than atherosclerosis. More data are needed on low preparations; however limited findings suggest little if any risk. There is no available data on the risk for coronary artery atherosclerosis due to OC use, even though 50% of all women die from atherosclerosis-related processes regardless of OC use. Non human primate studies, however, suggest that there may be a reduced risk, perhaps due to the presence of estrogen receptors in arterial endothelium and smooth muscles. Data clearly indicate that the overall risk of breast cancer pre and post 1950 is the same, but age may be a factor with younger OC users at risk; parity protects. The association for lifetime risk, however, cannot be determined since most use occurred in the 1960s. For cervical cancer, 8 found no increased risk and 9 did, and the suggestion is the 5 years use is related to increased risk. Biases related to sexual behavior confound control and analysis of data. The most common cancer in developing countries is cervical, which warrants greater Pap smear screening to reduce this preventable cancer. Protection from cancer of the endometrium occurs for 15 years following 12 months of OC use at a 40% reduced risk. A protected effect is also found for epithelial ovarian cancer, with a 40% risk reduction. It is concluded that health benefits of OCs far exceed the health risks.
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PMID:Long-term health risks and benefits of oral contraceptive use. 209 41

Progestins counteract the positive effect of the estrogen component in oral contraceptives (OCs) on cholesterol levels thus increasing the risk of atherosclerosis. Low androgenic potency progestins do not have a negative effect, however. Other research indicates that the lower the estrogen dose in OCs the lower the risk of deep vein and superficial thrombosis. OC users, especially low dose OC users, with no other risk factors (e.g. smoking and hypertension) are not at increased risk of cardiovascular disease. Some research demonstrates elevated risk of stroke in OC users, however. Elevated cholesterol, obesity, diabetes and other factors further increases the risk of stroke. Combined OCs protect against endometrial and ovarian cancer and this effect increases with use and continues after use. Moreover OC users are not at increased risk of pituitary adenoma. Results of some studies shows an increased risk of cervical cancer, but other only demonstrates a slight increase. So far research does not indicate the following to increase breast cancer risk among OC users: early age at 1st OC use, formulation, family history, and history of benign breast disease. There is an increased risk for liver tumors in OC users, nevertheless it is rare. OCs do not raise the risk of diabetes or gallbladder disease. High dose formulations increases the risk of high blood pressure, but not so with low dose formulations. OC use does not impair, fertility, but delayed conception often occurs. Most research demonstrates no increase in pelvic inflammatory disease in OC users. OCs do not cause congenital malformations. Combined OC use is contraindicated for breast feeding mothers, but progestin only OCs can be used with no advance effects. Results of 1 study demonstrates an increase in HIV infection in OC users, but another study has opposite results. The article concludes with recommended clinical management practices.
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PMID:Reassessment of the metabolic effects of oral contraceptives. 185 68

The overall risk of oral contraceptive (OC) use is minimal when women over 35 years of age, smokers, and those with multiple risk factors (thromboembolic disorders, cerebrovascular or coronary artery disease, liver tumors, breast cancer, estrogen-dependent neoplasms, undiagnosed abnormal genital bleeding, and congenital hyperlipidemia) are excluded. OC use increases the risk of hypertension by 1-5%, depending on age, parity, and duration of use, but even this small risk is decreased when multiphasic OCs are prescribed. Deep venous thrombosis in the leg is 4 times more prevalent in OC users than nonusers and the risk of superficial thrombosis is doubled. Again, fewer thromboembolic complications occur when the estrogen dosage is low. The risk of myocardial infarction is not believed to increase with OC use as long as other risk factors--smoking, obesity, hypertension, age over 35 years, hypercholesterolemia--are not present. Studies involving the original high-dose OCs revealed a 3-fold increase in the risk of thrombotic stroke and a 2-fold increase in the risk of hemorrhagic stroke, but low-dose OCs appear to have no effect on the potential for stroke. The impact of OC use on breast cancer cannot yet be determined given the very long latency period of this cancer. In terms of benign breast disease, OC users have been shown to be at substantially reduced risk of lesions, fibroadenomas, and fibrocystic changes. OCs also protect women from endometrial and ovarian cancer, although the pill seems to accelerate the progression of cervical dysplasia. Other beneficial effects of OC use include reductions in the incidence of pelvic inflammatory disease, endometriosis, ectopic pregnancy, and ovarian cysts.
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PMID:Oral contraceptive pills. Part II: Potential complications and health benefits. 228 19

The objectives of this article on epidemiological studies of health risks from oral contraceptives (OCs) is to review major studies of the association between OCs and circulatory disease and cancer. It is also to emphasize methodologic limitations of the existing data, and to identify unresolved and important questions. A brief discourse on the nature and imputation of relative risk is provided. Cardiovascular diseases covered include ischemic heart disease, stroke, and thromboembolism. Current studies on low dose pills from 3 large US populations reveal that there is no impact of death from use of OCs. A Great Britain and the Walnut Creek study from the US found a slight but not statistically significant increase in ischemic heart disease. These studies also found a statistically significant 3-fold increase in stroke among OC users and, from another study, a 2-fold increase. These studies were based on high levels of ethinyl estradiol where the risk becomes apparent. The risk for idiopathic venous thromboembolism was 3- 8 fold for current OC users. The accuracy of these findings is questioned when the data reflect such heterogeneity. Cancer is differentiated as breast cancer, endometrial cancer, ovarian cancer, cervical cancer, malignant melanoma, and hepatocellular adenoma. For breast cancer, both case control studies as well as cohort studies found no increase in breast cancer. Future additional research will continue to explore unanswered questions about this association. Beneficial effects of OCs occur for endometrial cancer for as long as 15 years after taking the pill. Only 1 year's use resulted in a 50% reduction in risk of endometrial cancer regardless of pill dose and particularly for nulliparous women, who have an increased risk. The longer duration of use of the OCs results in a protective effect against ovarian cancer, i.e., 5 years of use yields as relative risk of below 0.5 and the results of a protective effect can be seen as early as 3 months after pill use. There is about 40% protection against ovarian cancer even with low dose pills; the effect lasts 15 years after cessation of OC use. Cervical cancer studies have shown mixed results. The human papilloma viruses 16 and 18 have been shown to be related to cervical cancer but further research is needed to identify the association with OCs. Data are inconclusive but lean in the direction of no association with malignant melanoma. Hepatocellular adenoma has not been identified in large vital statistics studies, although several small studies have suggested an increased risk. It has been shown by Fortney et al. that with a 50% increase in cervical cancer risk and a 3-4 fold increase in cardiovascular disease risk that OC use for 5 years before the age of 30 years adds 4 days to a health women's life.
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PMID:Results of oral contraceptive epidemiologic studies regarding neoplastic and cardiovascular effects. 257 54

Although the majority of American women believe that oral contraceptives can cause serious health problems such as cancer or heart disease, the scientific literature does not support these beliefs. Oral contraceptives actually protect against endometrial and ovarian cancer. The increased incidence of cardiovascular disease in oral contraceptive users, including myocardial infarction, appears to be caused by thrombosis and not atherosclerosis. The studies suggesting an increased risk of cardiovascular disease in oral contraceptive users were published in the late 1970s and therefore used a data base of women ingesting formulations containing 50 micrograms of estrogen or more. More recently published data involving healthy women taking mainly lower estrogen dose preparations suggest that there is no increased incidence of myocardial infarction or stroke. Nearly all published studies indicate that there is no increased risk of myocardial infarction in former users of oral contraceptives. Animal data actually suggest that oral contraceptives may have a protective effect against atherosclerosis, even in the presence of lowered high-density lipoprotein levels. The low-dose triphasic and monophasic formulations are effective, safe methods of contraception that can be used by most healthy women of reproductive age.
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PMID:Correcting misconceptions about oral contraceptives. 268 52

The benefits and risks of both oral contraceptives and estrogen replacement therapy (ERT) are evaluated by summarizing briefly the results of the most evidential studies on breast, ovarian, endometrial, and hepatobiliary cancer, heart attack, stroke and venous thromboembolism. The methods used to estimate risk ratios, prospective random-allocation, double-blind trials, and retrospective case- controlled studies, are explained briefly. The ERT used today resemble sequential oral contraceptives, except that only 10-20 mcg ethinyl estradiol is taken for 25 days, and progestins are used on the last 10 days. Breast cancer risk is not different in pill users from nonusers, based on the U.K. General PRactitioner, Oxford Family Planning, Harvard nurses or U.S. SEER National Cancer Institute studies. Studies on ERT and breast cancer are mixed, but only injected estrogens raised the risks. Ovarian cancer is prevented by pill use in proportion to length of use. No studies were reported for ERT. The risk of hepatic cancer is 3.8 to 7.8 higher in pill users, but the number of cases is so rare that this should not affect prescriptions. Neither pill nor ERT raise the risk of myocardial infarction, and after premature surgical menopause, ERT lowers the risk. Based on studies done in the 1970s, oral contraceptives raise the risk of thrombotic stroke while women are taking them, from 10-13/100,000 to 41/100,000. ERT has no clear association with stroke. Similarly, orals increase the risk of venous thromboembolism, 8-fold in the Oxford Family Planning study published in 1986, although the absolute numbers are very small. ERT had no effects no risk of thromboembolism according to the lipid Research, Framingham and Nachtigall studies.
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PMID:The risks of oral contraceptives and estrogen replacement therapy. 268 99

The majority of epidemiological studies on the benefits and risks of oral contraceptive (OC) use have been conducted during the late 1960s and early 1970s when OCs had 50 mcg of estrogen. Based on these studies, the risk of death due to OC use for nonsmokers 35-39 years old was lower than using no contraceptive at all (14.1 deaths/100,000 women/year vs. 25.7 deaths/100,000 women/year). In addition to smoking, other contraindications include women with a history of angina, myocardial infarction, blood clots or stroke, estrogen dependent cancer, hypertension, a known lipid disorder, and women with hepatitis or cirrhosis of the liver. Suitable 35 year old candidates for OC use would be nonsmokers with blood group O, at low risk for cardiovascular disease, and who might receive additional benefits, including those with severe dysmenorrhea or hypermenorrhea and possibly those who have a strong family history of osteoporosis, early menopause, or ovarian cancer. Practitioners should take a thorough history of these women and give a physical examination with a blood pressure check. They should also administer screening tests, such as a PAP test, mammograms, a lipoprotein profile, and a glucose test. After the practitioners have deemed these women to be healthy based on the examination and the results of the screening test, they then should prescribe only a low dose OC containing 50 mcg of estrogen. Today most estrogen based OCs contain 35 mcg and research on their effects have not yet begun. Scientists expect to find that the dose response effects for risks for thromboembolism, myocardial infarction, stroke, and gallbladder disease to be lower in users of the low dose preparations.
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PMID:Risks and benefits of oral contraceptive use in women over 35. 323 16

Adverse and beneficial effects, especially with regard to mortality rates, of oral contraceptives (OC) are reviewed. In 1980 approximately 80 million women used OCs worldwide. OCs were first marketed in the United States in the 1960's, but by the 1980's low-dose combination pills with less estrogen and progesterone content became widespread along with the minipill, injectable preparations depo- medroxyprogesterone DMPA, and norethindrone containing capsules. Relative disease risk estimates are based on cohort studies and case- control studies. The Royal College of General Practitioners RCGP Oral Contraceptive Study of 1974 involved 46,000 women aged over 15 (50% were OC users, 50% were nonusers) the Oxford Family Planning Association Contraceptive Study of 1976 recruited 17,032 women aged 25-39, 56% of whom used OCs, and the Walnut Creek Contraceptive Drug Study of 1981 studied 16,638 women aged 18-54 of whom 28% were OC users and 33% were former users. A somewhat elevated mortality among ever-users of OCs in the order of 20% seems to be indicated by these studies mostly attributable to diseases of the circulatory system. Current OC use is also a risk factor in thrombotic stroke of the order of 4 or 5, but former use of OCs lowers the risk to 2. The effect of OC dose and formulation, duration of use, and predisposing factors on hemorrhagic and thrombotic stroke appears to be inconclusive with varying data from different studies. There is evidence for some increase in ischemic heart disease among current OC users, and also a 2-fold increase of myocardial infarction (MI) when smoking, serum cholesterol, and hypertension is taken into account, moreover higher estrogen dosage also contributes to a higher incidence of MI. There is also a 5-fold increase of venous thromboembolism among OC users induced by duration of use and estrogen potency, as OCs seem to promote atherogenesis, although the roles of progesterone and estrogen are conflicting. combination pills reduce the rate of endometrial cancer, provided protection against ovarian cancer, and do not seem to increase breast cancer incidence, although the relative risk of cervical cancer is elevated. Mortality risks with older OCs outweigh the benefits.
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PMID:On the epidemiology of oral contraceptives and disease. 331 96

This study evaluates the in vitro sensitivities of 42 ovarian cancer specimens to the new anticancer agent Paclitaxel (taxol, Tx), cisplatin (DDP), and the combination Tx-DDP with the adenosine triphosphate cell viability assay (ATP-CVA). In vitro response is defined by > or = 50% ATP decrease compared to untreated controls 6-7 days after drug treatment with 20% of the peak plasma concentration (PPC). Response rates were 12% to Tx, 19% to DDP, and 27% to Tx + DDP. The mean IC50's of Tx, DDP, and the combination Tx-DDP were (2.6x, 1.0x, and 0.38x PPC, respectively). The mean inhibition of cell viability was significantly greater with drug combinations compared to single drugs. In 7/11 tumors synergistic effects and in 2/11 additive effects were found between Tx and DDP. We conclude that based on ATP-CVA in vitro results, Tx-DDP shows significantly better activity compared to each of the single drugs in ovarian cancer.
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PMID:Evaluation of paclitaxel (taxol), cisplatin, and the combination paclitaxel-cisplatin in ovarian cancer in vitro with the ATP cell viability assay. 790 86

The dose-response relations of the cytotoxic drugs taxol and cisplatin and their combination were analyzed in an ovarian cancer cell line (BG-1). The chemosensitivity profiles were obtained with 5 concentrations using the ATP cell viability assay (ATP-CVA). Furthermore, the cytomorphologic changes were analyzed. Our findings demonstrate that the ATP-CVA is able to determine the fraction of surviving cells and has proved to be an effective tool to measure cytotoxicity. At the same time we were able to analyze the cytomorphologic changes. The implications of these results for the practice of gynecologic oncology are discussed.
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PMID:[Quantitative determination of dose-response relations of taxol and cisplatin in ovarian cancer cells with a bioassay in comparison with cytomorphology]. 795 Apr 42


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