Value of thyroid stimulating hormone combined with β-human chorionic gonadotropin in the prediction of preeclampsia in the first trimester of pregnancy

Abstract

Objective To observe the value of thyroid stimulating hormone (TSH) combined with β-human chorionic gonadotropin (β-hCG) in the prediction of preeclampsia (PE) in the first trimester of pregnancy. Methods A retrospectively cohort analysis was performed on 368 pregnant women who had undergone early clinical examination and delivery. The patients were divided into PE group (52 cases) and control group (316 cases) according to whether PE occurred. The general data, thyroid function, β-hCG and pregnancy-associated plasma protein A (PAPP-A) were comparatively analyzed. Using the clinical diagnosis as the golden standard , the receiver operating characteristic (ROC) curves were used to compare the diagnostic value and diagnostic efficacy of those indicators for predicting adverse pregnancy outcomes. Results Univariate analysis showed that pre-pregnancy body mass index [BMI, (24.41±2.11) kg/m2], TSH [(2.79±0.83) mIU/L] and PAPP-A [(1.27±0.28) mIU/L)] levels in PE group were significantly higher than those in control group [(23.72±1.96) kg/m2, (1.99±0.53) mIU/L, (0.98±0.39) mIU/L](P=0.021, 0.000, 0.000), while β-hCG level [(3.06±1.72)×104 IU/L] was significantly lower than that in control group [(5.48±2.29)×104 IU/L](P=0.000). Multivariate logistic regression analysis showed that TSH (OR=15.423, 95% CI=12.963~59.162, P=0.000) and PAPP-A (OR=9.794, 95% CI=4.195~22.867, P=0.000) were independent risk factors for PE, while β-hCG (OR=0.889, 95% CI=0.853~0.927, P=0.000) was a protective factor of PE. ROC curves showed that the area under the curve of TSH and β-hCG (AUC=0.780, 0.788) was higher than that of PAPP-A (AUC=0.705) and pre-pregnancy BMI (AUC=0.575), the Youden index showed that the best cut-off of TSH and β-hCG were TSH≥2.21 mIU/L and β-hCG≤ 3.96×104 IU/L. The diagnostic value of TSH combined with β-hCG (AUC=0.927) was significantly higher than that of TSH or β-hCG alone. The sensitivity of TSH combined with β-hCG in predicting PE was 96.15%, which was significantly higher than that of TSH and β-hCG (χ2=3.983, 4.981; P=0.046, 0.026), while no statistical differences were found in the diagnostic accuracy (χ2=0.363, 3.160; P=0.547, 0.075). Conclusion TSH combined with β-hCG have a high value in the prediction of PE in the first trimester of pregnancy, of which the best cut-off of TSH and β-hCG are TSH≥2.21 mIU/L and β-hCG≤3.96×104 IU/L, respectively. Key words: Thyroid stimulating hormone (TSH); Human chorionic gonadotropin (hCG); Preeclampsia (PE); Eclampsia; Sensitivity; Specificity