RESUMEN
Objective To evaluate the impact of subclinical hypothyroidism (SCH) on the outcome of pregnancy and the therapeutic effect of L-T4.Methods A total of 1 786 pregnant women during the first, second, and third trimesters were enrolled for thyroid screening by determining serum free thyroxine (FT4), total thyroxine (TT4), thyrotropin (TSH), and thyroid peroxidase antibody;123 pregnant women with SCH were successfully divided into treated group (n =42) and untreated group (n =81).The treated group was treated by L-T4 based on American Thyroid Association (ATA) 2011 guideline.Collected items include obstetric outcomes and complications.Results (1) Compared to control group, the rate of spontaneous abortion in pregnant women during first trimesters was increased in SCH group (20.99% vs 8.45%, x2 =12.96, P =0.00), with higher incidence of diabetes during second trimester (24.69% vs 10.45%, x2 =14.11, P =0.00).The incidences of hypertension during pregnancy, premature delivery, ablatio placentae, placenta praevia, fetus growth restriction, and low birth weight showed no difference between two groups (all P > 0.05).(2) Compared with the untreated group, the incidences of spontaneous abortion and diabetes were decreased in the treated group (7.14% vs 20.99%, x2 =3.89, P =0.05;9.52% vs 24.69%, x2 =4.05, P =0.04), while the incidences of hypertension, premature delivery, ablatio placentae, placenta praevia, fetus growth restriction, and low birth weight infant accident rate were not different between two groups (all P > 0.05).Conclusions SCH during the frist trimester is a risk factor of spontaneous abortion;SCH during the middle stage of pregnancy is a risk factor of gestational diabetes mellitus.Treatment of SCH with L-T4 may be beneficial.
RESUMEN
Totally 1 360 pregnant women during the first trimesters (4-12 weeks) who visited Ningbo University Affiliated Hospital and Ningbo Jiangbei Maternal Health Hospital from February 2010 to October 2011,and 216 non-pregnant healthy women,who contemporaneous by visited the hospital,were enrolled in this study.The thyroid screening was made by determining urinary iodine and serum free thyroxine,free triiodothyronine,total thyroxine,total triiodothyronine,thyrotropin,and thyroid peroxidase antibody (TPOAb).The median concentration of urinary iodine in the pregnant women was not different from that of non-pregnant women (P>0.05) ; 1 360 pregnant women were screened,268 (19.71%) of them were identified to suffer from thyroid disorders or with positive thyroid autoantibody.29(13.43%) of non-pregnant women were identified to suffer from thyroid disorders or with positive thyroid autoantibody.There was significant difference between the 2 groups (x2 =4.40,P<0.05).Prevalence of thyroid dysfunction may increase during early pregnancy.The screening for thyroid function and autoantibody should be recommended in that period.