ObjectiveTo assess the accuracy of diagnosing retained products of conception (RPOC) in symptomatic versus asymptomatic women, and to identify potential divergent ultrasound features between these groups. MethodsThis retrospective study included women aged 17–50 years who underwent hysteroscopy for suspected RPOC during 2018–2021. Clinical and sonographic data were analyzed, and multivariable linear regression models employed, to examine correlations between RPOC and sonographic findings, and to compare diagnostic accuracy between symptomatic and asymptomatic women. ResultsOf the 225 women included, 123 (54.7 %) were symptomatic and 102 (45.3 %) were asymptomatic. Hysteroscopy complications were more frequent in asymptomatic women. Regarding sonography, statistically significant differences were not found between the groups in endometrial thickness or uterine fluid presence, but positive Doppler flow was more common in asymptomatic than symptomatic women. Endometrial thickness >1.49 cm demonstrated diagnostic utility, with similar sensitivity and specificity in the two groups. Multivariable models revealed significant associations of RPOC presence with endometrial thickness and Doppler flow in symptomatic women. In both groups, hysteroscopy enhanced diagnostic accuracy, with higher positive predictive values and lower false-positive rates compared to ultrasound alone. ConclusionAn endometrial thickness cutoff of 1.49 cm aids diagnosing RPOC. Doppler flow enhances diagnostic value in symptomatic women. Integration of hysteroscopy improves diagnostic accuracy compared to ultrasound alone. Regular sonographic assessment for women with identifiable risk factors assists in RPOC detection irrespective of symptoms.