Nomogram for perinatal prediction of intrapartum fever: a retrospective case-control study

Abstract

Objective: To explore the risk factors for intrapartum fever and to develop a nomogram to predict the incidence of intrapartum fever.

Methods: The general demographic characteristics and perinatal factors of 696 parturients who underwent vaginal birth at the Affiliated Hospital of Xuzhou Medical University from May 2019 to April 2020 were retrospectively analysed. Data was collected from May 2019 to October 2019 on 487 pregnant women who formed a training cohort. A multivariate logistic regression model was used to identify the independent risk factors associated with intrapartum fever during vaginal birth, and a nomogram was developed to predict the occurrence. To verify the nomogram, data was collected from January 2020 to April in 2020 from 209 pregnant women who formed a validation cohort.

Results: The incidence of intrapartum fever in the training cohort was found in 72 of the 487 parturients (14.8%), and the incidence of intrapartum fever in the validation cohort was 31 of the 209 parturients (14.8%). Multivariate logistic regression analysis showed that the following factors were significantly related to intrapartum fever: primiparas (odds ratio [OR] 2.43; 95% confidence interval [CI] 1.15-5.15), epidural labour analgesia (OR 2.89; 95% CI 1.23-6.82), premature rupture of membranes (OR 2.37; 95% CI 1.13-4.95), second stage of labour ≥ 120 min (OR 4.36; 95% CI 1.42-13.41), amniotic fluid pollution degree III (OR 10.39; 95% CI 3.30-32.73), and foetal weight ≥ 4000 g (OR 7.49; 95% CI 2.12-26.54). Based on clinical experience and previous studies, the duration of epidural labour analgesia also appeared to be a meaningful factor for intrapartum fever; therefore, these seven variables were used to develop a nomogram to predict intrapartum fever in parturients. The nomogram achieved a good area under the ROC curve of 0.86 and 0.81 in the training and in the validation cohorts, respectively. Additionally, the nomogram had a well-fitted calibration curve, which also showed excellent diagnostic performance.

Conclusion: We constructed a model to predict the occurrence of fever during childbirth and developed an accessible nomogram to help doctors assess the risk of fever during childbirth. Such assessment may be helpful in implementing reasonable treatment measures.

Trial registration: Clinical Trial Registration: ( www.chictr.org.cn ChiCTR2000035593 ).

Keywords: Intrapartum fever; Nomogram; Predictive model; Risk factors.

Fig. 1

The Participants recruitment flowchart

Fig. 2

Nomogram for estimation of intrapartum fever

Fig. 3

ROC curves and calibration plots for the training cohort and validation cohort. Abbreviations: ROC, receiver operating characteristic; AUC, area under the ROC curve