Superovulation of dairy cattle is frequently used in Canada. The cost of this protocol is high, and so is the variability of the outcome. Knowing the superovulatory potential of a donor cow could influence the breeder’s decision to superovulate it or not. The ultimate objective of this study was to identify chromosome regions associated with superovulatory response in Canadian Holsteins. Data were provided by Holstein Canada and contained the total number of embryos and the number of viable embryos from every successful flushing performed across Canada. After editing, 137,446 records of superovulation done between 1992 and 2014 were considered for the analysis. A univariate repeatability animal model analysis was performed for both total number of embryos and number of viable embryos, yielding heritability estimates (SE) of 0.18 (0.01) and 0.14 (0.01), respectively. Breeding values were estimated for 54,463 cows, and 3,513 sires. Only estimated breeding values of animals that were genotyped with a SNP panel denser than 3K and having a reliability higher than 40% were considered (n = 5,122) for further analyses. All lower density genotypes were imputed to 50K using FImpute software. A genome-wide association study was carried out using a single SNP regression method, which also fits a polygenic background effect. Results were similar for the 2 highly genetically correlated (r_g = 0.94) traits considered in this study. A major significant peak on chromosome 11 was detected, suggesting the presence of an important candidate gene in this region.