Validation of a scoring system for prediction of obstetric complications in placenta accreta spectrum disorders

Abstract

Background

Placenta accreta spectrum (PAS) refers to a spectrum of conditions characterized by the abnormal adherence of the placenta to the implantation site and has been a challenge due to the risk of postpartum hemorrhage, peripartum hysterectomy and maternal mortality. Despite of sonographic findings, no consensus on the prenatal evaluation of PAS has been established yet. We are aiming to establish a scoring system to increase the accuracy of prediction of PAS severity, especially to differentiate placenta percreta and placenta increta.

Methods

We conducted a retrospective study and collected 2,219 cases of placenta increta and placenta percreta obtained from 20 tertiary care centers in China. Demographic information, clinical characteristics, and sonographic findings were collected. Logistic regression analysis was used to determine the risk factors and sonographic features that were significantly associated with a clinical diagnosis of placenta percreta. The formula and subsequent scoring system were generated. This scoring system was then verified in 67 cases of placenta increta or placenta percreta in Peking University First Hospital from 2016 to 2017. Diagnosis of placental invasion was confirmed by surgical findings or histopathologic results. The scoring system was evaluated using a receiver operating characteristic (ROC) curve.

Results

The scoring system combined maternal risk factors and ultrasound features and was then verified in 67 cases. According to ROC curve, the area under the curve (AUC) of our scoring system for prenatal diagnosis of placenta percreta is 0.96 (95%CI, 0.91–1.00, p < .001), for severe postpartum hemorrhage (≥1500 ml) is 0.76 (95%CI, 0.62–0.91, p = .005), for hysterectomy is 0.98 (95%CI, 0.93–1.000, p = .023).

Conclusions

Our scoring system combining maternal risk factors and ultrasound features can improve the predictive accuracy of placenta percreta and obstetric outcomes (severe hemorrhage and hysterectomy).

Keywords:

• Scoring system
• placenta percreta
• placenta increta
• placenta accreta spectrum
• prenatal diagnosis
• maternal morbidity

Acknowledgments

We thank the clinicians and countless participants throughout 20 tertiary care centers in China for great efforts and collaborations. The Cooperation Group of PAS in China (Junya Chen, Xiaoxiao Zhang, Lixin Fan, Xianlan Zhao, Dunjin Chen, Yilin Ding, Hongjuan Ding, Shihong Cui, Weishe Zhang, Hong Xin, Weirong Gu, Yali Hu, Guifeng Ding, Hongbo Qi, Ling Fan, Yuyan Ma, Junli Lu, Yue Yang, Li Lin, Xiucui Luo, Xiaohong Zhang, Shangrong Fan, Li Lin, Qianyun Wang, Beier Huang) contributed to data collection.

Disclosure statement

The authors declare no conflicts of interest.

Data availability statement

All relevant data are within the manuscript and its Supporting Information files.

Author’s contributions

Weiran Zheng, Huijing Zhang, Huixia Yang designed the study. Huijing Zhang, Jingmei Ma, Huixia Yang contributed to the statistical analysis. Weiran Zheng, Huijing Zhang, Jingmei Ma, Ruochong Dou wrote the draft, and Weiran Zheng, Jie Yan and Huixia Yang contributed to the discussion and approved the final version. Weiran Zheng and Huijing Zhang contributed equally to the manuscript. Xianlan Zhao contributed to data collection. Huixia Yang and Jie Yan accepted full responsibility for the work and the conduct of the study, had access to all data in the study and had final responsibility for the decision to submit for publication.

Additional information

Funding

The study was supported by National Key Technology Research and Development Program of China under grant [number 2015BAI13B06].