The aim of this study was to examine how similar pregnant women with self‐reported lifetime eating disorder (ED) were to pregnant women with a hospital diagnosis of ED. A total of 83 731 pregnant women enrolled in the Danish National Birth Cohort reported on ED, and by linkage to the Danish health registers, hospital diagnoses of ED were obtained. Characteristics of women with self‐reported ED, hospital diagnosed ED and without ED were compared using chi‐square tests, t‐test and logistic regression models with robust standard errors. In total, 4.8% women reported ED, and 0.5% had a hospital diagnosis of ED recorded in the health registers. Women with self‐reported ED were comparable with women with hospital diagnosed ED on most reproductive and health characteristics, while they differed from women without ED concerning all characteristics studied. Our findings highlight that women with self‐reported ED have impaired function and adverse health outcomes, consistent with diagnosable ED. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.