Comparison of the efficacy of levothyroxine treatment in the early and mid-term pregnancy for pregnant women with subclinical hypothyroidism

LIU Zhi-lan; HUANG Yan

doi:10.13820/j.cnki.gdyx.20233928

Abstract：Objective To compare the efficacy of levothyroxine treatment(LT)in early and mid-term pregnan-cy for pregnant women with subclinical hypothyroidism.Methods A total of 100 cases of subclinical hypothyroidism in pregnant women were observed at the Department of Obstetrics and Gynecology of the Affiliated Hospital of Xiangnan Uni-versity from January 2020 to October 2022.The subjects were divided into early pregnancy LT group and mid-term preg-nancy LT group at a ratio of 1∶1,with 50 cases in each group.The early pregnancy LT group received LT intervention on the second day of subclinical hypothyroidism diagnosis(8-10 weeks).The mid-term pregnancy LT group received LT intervention during mid-pregnancy(13-16 weeks)follow-up.The levels of TSH,FT4,and FT3 in fasting blood sam-ples were determined by chemiluminescent immunoassay.Pregnancy complications and outcomes were compared between the two groups.Results The duration of pregnancy at registration was(57.88±12.20)days in the early pregnancy LT group and(58.78±10.08)days in the mid-term pregnancy LT group.Compared with before treatment,the serum TSH levels significantly decreased in both groups after LT treatment(before delivery)(P＜0.05),with no statistically signifi-cant difference between the two groups(P＞0.05).Additionally,there were no significant differences in serum FT3 and FT4 levels before and after treatment,as well as between the two groups(P＞0.05).Compared with the early pregnancy LT group,the mid-term pregnancy LT group showed a significant increase in the risks of miscarriage,pregnancy-in-duced hypertension,and neonatal admission to the NICU(P＜0.05).After controlling for the impact of TPOAB positivi-ty,miscarriage,pregnancy-induced hypertension,and neonatal admission to the NICU were closely related to the mid-term pregnancy LT group(P＜0.05).Conclusion The timing of initiating LT treatment for subclinical hypothyroidism may influence the prevention of adverse pregnancy outcomes.Early pregnancy LT intervention may help reduce the occur-rence of miscarriage,pregnancy-induced hypertension,and neonatal admission to the NICU.