Key massages 1. This secondary analysis of the randomized controlled ESPRESSO trial, to investigate the histological features of the endometrial sample obtained before or after the saline contrast sonohysterography in women with postmenopausal bleeding, showed that the histological features of the endometrial sample were not affected by the saline contrast sonohysterography. 2. This study also showed that a higher amount of blood, endometrial epithelium, intact endometrial glands, stroma and tissue context were found in sufficient endometrial samples compared to insufficient endometrial samples. Oppositely, a significantly higher amount of mucus was found in the insufficient samples.