Risk Prediction of Recent Delivery in Pregnant Women with Threatened Early Preterm Labor
Objective:To explore the establishment of a Cox proportional hazard prediction model for the re-cent(within a week)delivery of pregnant women with threatened early preterm labor(28-33+6 weeks).Meth-ods:The clinical data of 293 patients with threatened early preterm labor at 28-33+6 weeks admitted to the De-partment of Obstetrics,Affiliated Hospital of North Sichuan Medical College from January 2021 to December 2022 were retrospectively collected.According to whether the patient gave birth recently(within a week)during hospi-talization,they were divided into delivery group(n=88)and non-delivery group(n=205).Demographic data,specialty conditions and clinical biochemical indicators were collected,and the differences of each observation in-dex between the two groups were compared.Cox multivariate analysis was used to screen variables,and then the Cox proportional hazard prediction model was constructed to calculate the hazard ratio(HR).The C-index was used to test the predictive ability of the model,and the nomogram was drawn to visualize the Cox proportional hazard prediction model.The calibration curve was used to test the consistency between the model prediction re-sults and the actual situation.Results:The average age of the delivery group was 30.2±5.0 years old,and the average prolonged pregnancy time was 61.3±47.5 hours.Compared to the group that gave birth and did not give birth,the proportion of patients with body mass index(BMI)at admission,parity>1,gestational diabetes mellitus or diabetic pregnancy combined(GDM/PGDM),abnormal fetal orientation,regular contractions at admis-sion,vaginal cleanliness≥ Ⅲ,white blood cell count ≥10 ×109/L at admission and cervical length<20 mm,the difference was statistically significant(P<0.05).Multivariate Cox regression analysis:BMI>30 kg/m2(HR 2.178,95%CI 1.208-3.928,P=0.010),parity>1(HR 3.095,95%CI 1.759-5.447,P<0.001),regular uterine contraction(HR3.447,95%CI 2.216-5.362,P<0.001),cervical length<20 mm(HR3.594,95%CI 2.289-5.646,P<0.001)and white blood cell count≥10 ×109/L(HR2.124,95%CI 1.352-3.335,P=0.001)on admission were independent risk factors for recent(within a week)delivery of pregnant women with threatened early preterm birth.When the above 5 indicators were included in the prediction model,the C-index was 0.797(95%CI 0.750-0.844),indicating that the model had good prediction ability.The calibration chart shows that the prediction results of the model are in good agreement with the actual results.Conclusions:Preg-nant women with BMI>30 kg/m2 at admission,parity>1,regular uterine contraction at admission,cervical length<20 mm at admission and white blood cell count≥10 ×109/L at admission are prone to premature delivery in the near future.Cox proportional risk prediction model based on the above risk factors has certain accuracy,which can be used to guide clinical workers to take corresponding intervention measures in advance to avoid or reduce the possibility of premature delivery in the near future and improve maternal and infant outcomes.
Threatened early preterm laborDeliveryRisk factorsProportional hazard model