Vessey M P
Department of Community Medicine and General Practice, Oxford University, England.
Int J Fertil. 1989;34 Suppl:64-70.
Epidemiologic studies of oral contraception are of two main types: case-control and cohort. The best known cohort studies are the Royal College of General Practitioners' study and the Oxford-Family Planning Association study, both of which have been conducted in the United Kingdom. Combination oral contraceptives--both the older, higher-dose type, and the newer, lower-dose type--are highly effective if used properly. Noncontraceptive benefits of combination oral contraceptives include protective effects against menstrual disorders, anemia, benign breast disease, functional ovarian cysts, ovarian cancer, endometrial cancer, pelvic inflammatory disease, and uterine fibroids. Adverse effects include various cardiovascular problems, liver tumors, and the temporary impairment of fertility after stopping use, especially in older, nulliparous women. Effects, if any, on breast cancer and cervical cancer are still under evaluation. The often quoted cardiovascular risks of combination oral contraceptives are derived from studies of the older, higher-dose pills used in an outmoded way. There is evidence that modern pills, used by properly selected young women who are subsequently kept under surveillance, carry a minimal cardiovascular risk. A national study is currently in progress in the United Kingdom to try to confirm this.
病例对照研究和队列研究。最著名的队列研究是英国皇家全科医师学院的研究以及牛津计划生育协会的研究。如果正确使用，复方口服避孕药——包括较旧的高剂量类型和较新的低剂量类型——都非常有效。复方口服避孕药的非避孕益处包括对月经失调、贫血、良性乳腺疾病、功能性卵巢囊肿、卵巢癌、子宫内膜癌、盆腔炎和子宫肌瘤的保护作用。不良反应包括各种心血管问题、肝肿瘤以及停药后生育能力的暂时受损，尤其是在年龄较大、未生育的女性中。对乳腺癌和宫颈癌的影响（如果有）仍在评估中。经常被提及的复方口服避孕药的心血管风险来自于对以过时方式使用的较旧高剂量药丸的研究。有证据表明，由经过适当选择且随后接受监测的年轻女性使用的现代药丸，其心血管风险极小。英国目前正在进行一项全国性研究以试图证实这一点。
