Background: Morbidly obese women are at increased risk for breast cancer, and the majority of surgical weight-loss patients are older than 40 years old. Objective: The purpose of the present study was to determine the technical and interpretive changes in mammography following bariatric surgery. Setting: Accredited Academic Hospital. Methods: Two breast-imaging radiologists reviewed screening mammograms performed on 10 morbidly obese women undergoing bariatric surgery both pre-and postoperatively. American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS) density, imaging quality measurements, compression force, breast thickness, pectoral nipple line (PNL) length, and x-ray beam kilovoltage (kVp) and miliamperes per second (mAs) were recorded. Results: The average patient age was 56 years old, with mean age at menarche of 13 years old; 70% of patients were postmenopausal (average age 49 years at menopause) and 50% had a family history of breast cancer. There was a significant reduction in both BMI (-13.2 kg/m(2), P < .01) and waist circumference (-32.0 cm, P < .01) following bariatric surgery. There was a significant reduction in breast thickness (-23.8 mm), reduction in PNL length (-1.9 cm), reduction in kVp (-1.2), and reduction in mAs (-16.7) even though there was no compression force change in pre-and postoperative mammograms detected. All breast densities were fatty or scattered though there were more scattered and fewer fatty images after surgery (P = .002). Conclusion: Morbidly obese women can undergo quality mammograms before and after bariatric surgery; however, weight loss after bariatric surgery leads to only slightly denser mammograms. Furthermore, weight loss reduces mammographic radiation doses. (C) 2017 American Society for Metabolic and Bariatric Surgery. All rights reserved.