ABSTRACT
The Pill-free time is the contraception-deficient time, which has great relevance to advice for the maintenance of combined oral contraceptive (COC) efficacy. The reanalysis showed disappearance of the risk in ex-users, but recency of use of the COC as shown to be the most important factor, with the odds ratio unaffected by age of initiation or discontinuation, use before or after first full-term pregnancy, duration of use, or dose. Systematic reviews of studies led to the conclusion that the COC acts as a cofactor, possibly speeding transition through the stages of cervical intraepithelial neoplasia. COC use increases the relative risk of benign adenoma or hamartoma, either of which can cause pain or rarely a haemoperitoneum. Suppression of ovulation in COC users and of normal mitotic activity in the endometrium is the accepted explanation of these findings. Case-control studies support the view that the rare primary hepatocellular carcinoma is also minimally less rare in COC users than in controls.
