Cigarette smoking and cervical cancer: meta-analysis and critical review of recent studies.

The objective of this study is to investigate the strength of the epidemiological evidence for a relationship between smoking and cervical cancer by analysis of recent literature. I conducted a meta-analysis of all eligible case-control studies published in English from 1977 to July 1990, with the primary intent of examining the relationship between smoking and cervical cancer. I identified nine eligible studies. Data pooled from eight studies using similar definitions for cervical cancer and classification of smoking showed a significant effect on cervical cancer of ever having smoked, with a crude odds ratio (OR) of 1.46 (95% confidence interval [CI] 1.34-1.58). And, from those studies which adjusted for age and number of sexual partners, a weighted OR of 1.42 (95% CI 1.33-1.51) was obtained. A significant association between smoking and cervical cancer emerges. Data from these studies suggest a 42%-46% increase in cervical cancer among smokers, even after controlling for age and number of sexual partners.