Abstract: Objective To investigate the clinical value of thyroid function testing and monitoring blood pressure coefficient of variation in predicting pregnancy outcomes in patients with hypothyroidism during pregnancy. 
Methods A total of 138 patients with hypothyroidism during pregnancy were selected as the observation group, including 47 cases of clinical hypothyroidism as the observation group one, and 91 cases of subclinical hypothyroidism as the observation group two. Forty-eight patients with normal thyroid function undergoing pregnancy tests were selected as the control group. The general data, thyroid function ［thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4)］, and blood pressure ［diastolic blood pressure (DBP), systolic blood pressure (SBP), DBP coefficient of variation (DCV), SBP coefficient of variation (SCV), DBP standard deviation (DSD), SBP standard deviation (SSD)］ were compared among three groups. The correlation between thyroid function, blood pressure and blood pressure variability in patients with hypothyroidism during pregnancy was analyzed. Logistic regression analysis was used to analyze the influencing factors of adverse pregnancy outcomes in hypothyroidism during pregnancy, and receiver operating characteristic (ROC) was used to analyze the predictive value of thyroid function, blood pressure and blood pressure variability for adverse pregnancy outcomes. 
Results The proportion of gestational hypertension and TSH, FT3, FT4, 24 h-DBP, 24 h-SBP, 24 h-DCV, 24 h-SCV, 24 h-DSD and 24 h-SSD among the three groups were significantly different (P<0.05); Thyroid function in patients with hypothyroidism during pregnancy was related to blood pressure and blood pressure variability (P＜0.05). Logistic regression analysis showed that increased TSH, 24 h-DBP, 24 h-SBP, 24 h-DCV, 24 h-SCV, 24 h-DSD, 24 h-SSD, and decreased FT3 and FT4 were independent risk factors for adverse pregnancy outcomes in patients with hypothyroidism during pregnancy (P＜0.05). The ROC curve showed that the area under the ROC curve (AUC) of TSH, FT3, FT4, 24 h-DBP, 24 h-SBP, 24 h-DCV, 24 h-SCV, 24 h-DSD, and 24 h-SSD in combination for predicting the adverse pregnancy outcome of patients with hypothyroidism during pregnancy was 0.962, which was higher than prediction of each index alone. 
Conclusion The blood pressure and blood pressure coefficient of variation are higher in patients with hypothyroidism during pregnancy. Thyroid function testing combined with blood pressure coefficient of variation can more effectively predict pregnancy outcome, and provide a reference for timely intervention and treatment. 

Key words: pregnancy, hypothyroidism during pregnancy, blood pressure coefficient of variation