The value of postpartum ultrasound for the diagnosis of retained products of conception: A systematic review

BACKGROUND: The goal of this review is to evaluate the value of ultrasound for detection of retained products of conception (RCOP) after delivery. METHODS: A systematic search was performed using ‘postpartum’, ‘retained placenta’, ‘retained products’ and ‘ultrasound’ resulting 82 publications, after screening titles and abstracts, 30 remained. RESULTS: On gray scale ultrasound, one must be focus on a thickened endometrial echo complex (EEC) with a cut off value of 10 mm and on an intracavitary mass. If these features are not visible, RPOC is rare. However, these findings are neither specific nor conclusive for RPOC and can even be seen in a normal postpartum uterus. Detection of hypervascularity in a thickened EEC or intracavitary mass with color Doppler ultrasound is very sensitive for RPOC but still not specific nor can it exclude RPOC. MRI seems best in differentiating RPOC, arteriovenous malformations and gestational trophoblastic disease. CONCLUSION: There is no consensus on a standardised method for postpartum ultrasound. More research and standardization are necessary to differentiate of normal and pathological findings in the postpartum uterus.