左甲状腺素钠片治疗妊娠合并亚临床甲状腺功能减退症的效果及对甲状腺激素水平、妊娠结局及子代生长发育的影响OACSTPCD

Objective:To explore the effect of levothyroxine sodium tablet(LT4)in treatment of pregnancy with subclinical hypothyroidism and its influence on thyroid hormones levels and pregnancy outcomes. Methods:Pregnant women with subclinical hypothyroidism who experienced regular prenatal check-up and delivered in Jingmen People's Hospital from July 2020 to January 2022 were retrospectively selected as the study subjects.According to whether patients received LT4 treatment,they were divided into LT4 group(n=68)and non-LT4 group(n=52).LT4 group was treated with a maintenance dose of 50～200 μg/d according to serum thyroid stimulating hormone(TSH)level until the end of delivery,and non-LT4 group received conventional intervention.Another 50 healthy pregnant women who experienced regular prenatal check-up and delivery in the same hospital during the same period were included in the control group.Baseline characteristics and pre-delivery thyroid hormones level were compared among the three groups,and the delivery modes,pregnancy outcomes and neonatal thyroid function within 24 hours and thyroid function and growth and development indicators at 6 months after birth were also compared.The adverse reactions during treatment were evaluated. Results:Compared with baseline status,TSH levels in LT4 group and non-LT4 group before delivery were significantly lower(P＜0.05)while free thyroxine(FT4),free triiodothyronine(FT3),total triiodothyronine(TT3)and total thyroxine(TT4)levels were significantly higher(P＜0.05).And the changes of thyroid hormones in LT4 group were significantly higher than those in non-LT4 group and control group(P＜0.05).There were no significant differences in premature rupture of membranes rate,postpartum hemorrhage rate,low birth weight infant rate and the delivery mode among the three groups(P＞0.05),but the incidence of premature delivery in non-LT4 group was significantly higher than those in control group and LT4 group(P＜0.05).Compared with those at 24 hours after birth,TSH levels in the three groups were significantly reduced at 6 months after birth(P＜0.05)while FT4,FT3,TT3 and TT4 levels were significantly higher(P＜0.05).TSH and FT4 levels in non-LT4 group were significantly higher than those in LT4 group and the control group at 24 hours and 6 months after birth(P＜0.05).The levels of TSH and FT4 in LT4 group at 24 hours after birth were significantly higher than those in control group(P＜0.05),but there were no significant differences in FT3,TT3 and TT4 levels among three groups at each examination(P＞0.05).At 6 months after birth,body length,body weight and the sitting duration were significantly shorter in non-LT4 group than those in control group and LT4 group,and there was no significant difference among the three groups in object fixation duration(P＞0.05).During treatment,there was no significant difference in the incidence of adverse reactions among the three groups(P＞0.05). Conclusions:LT4 has a significant effect in the treatment of pregnancy with subclinical hypothyroidism,and it has certain benefits in improving the thyroid function and pregnancy outcomes,promoting normal fetal development safely.