Quantitative prediction of postpartum hemorrhage in cesarean section on machine learning

Abstract

Background: Cesarean section-induced postpartum hemorrhage (PPH) potentially causes anemia and hypovolemic shock in pregnant women. Hence, it is helpful for obstetricians and anesthesiologists to prepare pre-emptive prevention when predicting PPH occurrence in advance. However, current works on PPH prediction focus on whether PPH occurs rather than assessing PPH amount. To this end, this work studies quantitative PPH prediction with machine learning (ML).

Methods: The study cohort in this paper was selected from individuals with PPH who were hospitalized at Shijiazhuang Obstetrics and Gynecology Hospital from 2020 to 2022. In this study cohort, we built a dataset with 6,144 subjects covering clinical parameters, anesthesia operation records, laboratory examination results, and other information in the electronic medical record system. Based on our built dataset, we exploit six different ML models, including logistic regression, linear regression, gradient boosting, XGBoost, multilayer perceptron, and random forest, to automatically predict the amount of bleeding during cesarean section. Eighty percent of the dataset was used as model training, and 20 $\%$ was used for verification. Those ML models are constantly verified and improved by root mean squared error(RMSE) and mean absolute error(MAE). Moreover, we also leverage the importance of permutation and partial dependence plot (PDP) to discuss their feasibility.

Result: The experiment results show that random forest obtains the highest accuracy for PPH amount prediction compared to other ML methods. Random forest reaches the mean absolute error of 21.7, less than 5.4 $\%$ prediction error. It also gains the root mean squared error of 33.75, less than 9.3 $\%$ prediction error. On the other hand, the experimental results also disclose indicators that contributed most to PPH prediction, including Ca, hemoglobin, white blood cells, platelets, Na, and K.

Conclusion: It effectively predicts the amount of PPH during a cesarean section by ML methods, especially random forest. With the above insight, ML predicting PPH amounts provides early warning for clinicians, thus reducing complications and improving cesarean sections' safety. Furthermore, the importance of ML and permutation, complemented by incorporating PDP, promises to provide clinicians with a transparent indication of individual risk prediction.

Keywords: Cesarean section; Machine learning; Partial dependence plot; Permutation importance; Postpartum hemorrhage; Random forest; Regression.

Fig. 1

Flow chart

Fig. 2

Missing data analysis

Fig. 3

Correlation analysis of some indicators

Fig. 4

Hemorrhage bar chart and box chart

Fig. 5

Regression analysis results of several ML methods

Fig. 6

Permutation importance of the indicators

Fig. 7

The PDP of indicator Ca

Fig. 8

The PDP of indicator HB

Fig. 9

The PDP of indicator WBC

Fig. 10

The PDP of indicator PLT

Fig. 11

The PDP of indicator Na

Fig. 12

The PDP of indicator K