We sought to determine the value of conization margin status in predicting residual and recurrent adenocarcinoma in situ (ACIS) of the cervix. In all, 33 studies (1278 patients) were identified. Metaanalysis with pooled Mantel-Haenszel odds ratio (OR) was used to compare the risk of residual and recurrent disease according to margin status. A repeated excisional procedure was performed in 607 patients; a positive conization margin was associated with a significant increase in the risk of residual disease (OR, 4.01; 95% confidence interval [CI], 2.62-6.33; P < .001). Of the 671 patients followed up with surveillance only, 2.6% with negative margins and 19.4% with positive margins developed a recurrence (OR, 2.48; 95% CI, 1.05-6.22; P < .001). Invasive adenocarcinoma was more commonly associated with positive margins (5.2%) compared with negative margins (0.1%). After conization for ACIS, patients with positive margins are significantly more likely to have residual or recurrent disease, whereas those with negative margins may be treated conservatively.