The objective of this article is to determine through meta-analysis of published literature whether active management of labor lowers the cesarean delivery rate for dystocia in nulliparas. Using MEDLINE and reference citations to 1966, 18 published reports in English on active management of labor were identified. Selection criteria for five selected studies included: tenets of active management followed, detailed description of patient selection and analysis, numerical data on cesarean deliveries for dystocia in nulliparas, and use of a control group. Data on cesarean deliveries performed on nulliparas for dystocia were abstracted onto 2 x 2 tables by both authors independently (one blinded to study authors, journal, institution, and conclusions), and quality ratings independently assessed. Differences were resolved by consensus. Individual odds ratios were calculated, with summary odds ratios and 95 percent confidence intervals determined using the Mantel-Haenszel method. Including the three highest quality studies (two randomized, one nonrandomized), there was a 34 percent decrease in cesarean delivery rates associated with active management (OR 0.66, 95 percent CI 0.54-0.81), without an increase in adverse neonatal outcome (OR for cesarean for non-reassuring fetal heart rate monitoring 0.91, 95 percent CI 0.68-1.22). Active management of labor is associated with a 34 percent decrease in the rate of cesarean delivery for dystocia in nulliparas. Along with the expected subsequent decrease in numbers of candidates for trials of labor, the decline in total cesarean deliveries over the entire population directly or indirectly attributable to active management is 13 percent.