Contraception case study

Studies 1 Faust and Tyler [315], and by Connell and Kelman [316] have failed to reveal a significantly different incidence of eye abnormalities in pill users. Both groups of workers pointed out the limitations inherent in studies involving relatively small groups of patients. Two cases of retinal oedema secondary to the use of oral contraceptives have been reported by Goren [317], Four cases studied by Salmon, Winkelman and Gay [318] led these authors to the conclusion that neuro-opthalmic sequelae may be secondary to vascular disease. A possible connection between oral contraceptives and ocular complications in users of contact lenses has been mentioned by several workers (see for example [319]). 

For women who are of childbearing potential, the risks can be evaluated in reproductive toxicology studies and steps taken to minimize those risks. Alternatively, stringent contraceptive requirements can be incorporated into the clinical protocol to prevent the occurrence of pregnancy in the participants, although in practice, contraception is usually specified in all cases. Any risks should be... 

Suggestive case histories raised at an early phase the notion of a possible correlation of oral contraceptives with endometrial cancer. Among cases of endometrial cancer there seemed to be an excess of users of oral contraceptives, particularly of the early high-dose estrogen type. With the virtual demise of these early products, the situation seems to have reversed a 1983 study from the Centers for Disease Control (CDC) in Atlanta showed that women who had used fixed combinations for oral contraception at some time in their lives had a relative risk of endometrial cancer of only 0.5 compared with never-users (112). The protective effect occurred only in women who had used oral contraception for at least 12 months, and lasted for at least 10 years after withdrawal. The WHO adopted the same view in 1988 in the light of multinational data (113). As in the case of hormonal replacement therapy, the protective effect seems to be due to the progestogen component. 

It is clear from the studies reported in Table 1 (133-149) that there is no simple relation between treatment with hormonal oral contraceptives and the incidence of breast cancer. As in the case of other neoplasms, studies are confounded by the influence of many factors, including age, parity, age at first delivery, family history, pre-existent fibrocystic disease, geographical or... 

Case-control study Link between oral contraceptives and breast cancer, but only in those aged 30-34 years coincidental (134)... 

Case-control study Ever-users of oral contraceptives had 1.1 risk compared with never-users higher doses produce a slightly higher risk duration of use irrelevant family history higher risk use after age 40 risk increased by 50% (139)... 

Case-control study Pike s results not confirmed may be some protective effect of oral contraceptives (136)... 

Case-control study No link with oral contraceptives (141)... 

Case-control study No link with oral contraceptives, except for a 30% increase if taken before first full pregnancy (142)... 

International case-control study Risk doubled by use of oral contraceptives for 12 years risk increased by duration of use risk increased by use before first pregnancy results may only be valid for Swedish women under 40 not seen in older or Norwegian women (146)... 

Population-based, case-control study 12-fold risk increase when young women use oral contraceptives for 12 years or more (148)... 

Non-invasive breast carcinoma, i.e. breast carcinoma in sit, has been studied in Connecticut in 2003 by examining data on 875 cases of ductal carcinoma in situ registered between 1994 and 1998, as well as data on 999 controls. The risk of ductal carcinoma in situ was not increased in women who had ever used oral contraceptives compared... 

A 1978 WHO report quoted an unpublished study by March in which pituitary adenomas were found in 26% of women with secondary amenorrhea following the use of oral contraceptives, yet in only 13% of cases who had not used these products (118). The difference was significant, but selection bias might have explained the results. 

Janerich DT, Polednak AP, Glebatis DM, Lawrence CE. Breast cancer and oral contraceptive use a case-control study. J Chronic Dis 1983 36(9) 639-46. 

Christoffersen T, Bergsjo P. Oral contraceptive use and breast cancer in young women. A joint national case-control study in Sweden and Norway. Lancet... 

Lee NC, Rosero-Bixby L, Oberle MW, Grimaldo C, Whatley AS, Rovira EZ. A case-control study of breast cancer and hormonal contraception in Costa Rica. J Natl Cancer Inst 1987 79(6) 1247-54. 

Hulman G, Trowbridge P, Taylor CN, Chilvers CE, Sloane JP. Oral contraceptive use and histopathology of cancerous breasts in young women. Members of the U.K. National Case-Control Study Group J Pathol 1992 167(4) 407-11. 

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