Correlation between subclinical hypothyroidism and gestational diabetes during pregnancy

Abstract

Objective To investigate the relationship between subclinical hypothyroidism and gestational diabetes during pregnancy. Methods A total of 187 pregnant women with high risk of gestational diabetes from February 2016 to October 2018 in Zaozhuang Maternal and Child Health Hospital were selected. All patients were given oral glucose tolerance test. The results showed that 142 cases of normal sugar tolerance (NGT group), pregnancy 45 patients with diabetes (GDM group). Another 20 normal pregnant women who received pregnancy test were allocated into control group. The clinical data of three groups were retrospectively analyzed, and their thyroid function and thyroid autoantibodies were compared. Results The free thyroxine levels in the GDM group were lower than those in the NGT group and the control group, and the differences were significant (t=13.427, 23.901, P=0.000, 0.000). The thyroid peroxidase antibody value of pregnant women in the GDM group was (38.67±6.13) U/ml, which was higher than that of the pregnant women (30.09±5.26) U/ml and NGT group (22.31±4.51) U/ml, and the differences were significant (t=9.153, 10.698; P=0.000, 0.000). The positive rate of thyroid autoantibodies in pregnant women in GDM group were higher than those in NGT group and control group (χ2=18.538, 3.369; P=0.000, 0.031). The rate of subclinical hypothyroidism in pregnant women in the GDM group was 33.33% (15/45), which was higher than 9.86% (14/142) in the NGT group and 5.00% (1/20) in the control group. The difference among the three groups was significant (χ2=14.370, 4.561; P=0.000, 0.014). Conclusions Subclinical hypothyroidism and gestational diabetes can affect each other. Gestational diabetes can impair thyroid function in pregnant women and increase the probability of subclinical hypothyroidism. Key words: Subclinical hypothyroidism; Gestational diabetes; Pregnancy