Pelvic floor dysfunction affects about half of women over 50 years of age, causing significant morbidity. MR defecography compliments the clinical examination in the evaluation of pelvic floor dysfunction. We investigated if the measurement of levator hiatus width is a useful and reliable supplement or alternative measurement in predicting pelvic floor dysfunction. We retrospectively reviewed MR defecography examinations and recalculated the levator hiatus width and the anorectal angle with 2 blinded readers. We found that the levator hiatus width had a statistically significant correlation with pelvic organ prolapse and can add to the confidence in reporting H-line and M-line abnormalities.