The RPOC long axis is a simple indicator for predicting the need of invasive strategies for secondary postpartum hemorrhage in either post-abortion or post-partum women: a retrospective case control study

Abstract

Background The retained products of conception (RPOC) and related conditions (RPOC-ARC) are the main cause of secondary postpartum hemorrhage (sPPH), but there is no clear consensus for their management. The purpose of this study was to characterize those RPOC-ARC that require invasive treatment and those that could be managed more conservatively. Methods We retrospectively analyzed 96 cases of RPOC-ARC that occurred after miscarriage, abortion, or delivery at a gestational age between 12 and 42 completed weeks, that were managed within our institution from May 2015 to August 2020. We reviewed the associations between the occurrence of sPPH requiring invasive treatment with clinical factors such as the maternal background and the characteristics of the lesions. Results The range of gestational age at delivery in our study was 12–21 weeks in 61 cases, 22–36 in 5, and 37 or later in 30. Among them, nine cases required invasive procedures for treatment. The onset of sPPH was within one month of delivery in all but two cases, with a median of 24 days (range 9–47). We found significant differences between requirements for invasive versus non-invasive strategies according to gestational age at delivery, assisted reproductive technology (ART) pregnancy, amount of blood loss at delivery, and the long axis of the RPOC-ARC lesion (p = 0.028, p = 0.009, p = 0.004, and p = 0.002, respectively). Multivariate analysis showed that only the long axis of the lesion showed a significant difference (p = 0.029). The Receiver Operating Characteristic (ROC) curve for predicting the need for invasive strategies using the long axis of the lesion showed that with a cutoff of 4.4 cm, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was 87.5, 90.0, 43.8, and 98.7%, respectively. Conclusion The long axis of the RPOC-ARC is a simple indicator for predicting which sPPH will require invasive procedures, which use is rare in cases with lesions less than 4.4 cm or those occurring after the first postpartum month. Conservative management should be considered in such cases.

Predictive factors for massive hemorrhage in women with retained products of conception: a prospective study

“…Matsumura et al reported that ultrasonographic assessment of RPOC focusing on vascularity in combination with size was essential for detecting the high risk of severe postpartum hemorrhage (SPPH) in women with RPOC 27 . Kobayashi et al also suggested that the long axis of RPOC is a simple indicator for predicting women with SPPH who would require invasive procedures 28 . However, in our analysis, consistent significant differences in these factors were not observed between the two groups of patients.…”

Spontaneous resolution of retained products of conception in late pregnancy: retrospective cohort study

“…Previous studies reported that the RPOC diameters [?] 4 -4.4 cm 6,8) or blood flow in RPOC 7,21) had been associated with heavy bleeding during conservative management of RPOC. However, these studies differ from the present study in several respects.…”

“…However, these studies differ from the present study in several respects. First, these studies included cases before 20 weeks' gestation [6][7][8]21) . Although the size of RPOC is smaller, trophoblast cell viability is higher in early and mid-pregnancy than in late pregnancy 20) .…”

“…Although the size of RPOC is smaller, trophoblast cell viability is higher in early and mid-pregnancy than in late pregnancy 20) . Furthermore, these studies included cases in which the placenta was manually removed within 24 hours after delivery 6,8) . Therefore, the results of previous studies were based on a heterogenous population and may have had various biases.…”

“…Additionally, the placenta often remains partly after MROP 5) . If conservative management is chosen immediately after deliver, or RPOC occurs after MROP, there is a risk of subsequent massive haemorrhage or infection [6][7][8][9] . Therefore, some studies suggest that RPOC should be removed by transcervical resection (TCR) to avoid bleeding and infection during conservative management 10,11) .…”