Thyroid dysfunction in early pregnancy and spontaneous abortion

Abstract

Background: Pregnancy is associated with significant but reversible changes in thyroid function. Abnormal thyroid hormone levels could give rise to increased malplacentation increase to malplacentation that underlies the association between maternal thyroid dysfunction and adverse obstetric outcomes such as fetal brain damage, preterm births, and fetal death. Aim: The present study was planned to predict the risk of abortion in pregnancy by studying the relation between thyroid profile and rate of abortion. Methods: This prospective observational study was carried out in 100 pregnant women with a singleton pregnancy of 6–12 weeks of gestation in the Department of Biochemistry in collaboration with the Department of Obstetrics and Gynaecology, Pt. B.D. Sharma, PGIMS, Rohtak. The patients were divided into three groups, namely, Group 1 (n = 30, control group) included normal pregnant women with no history of abortion; Group 2 (n = 35) included pregnant females with previous history of abortion; and Group 3 (n = 35) comprised pregnant women coming with chief complaint of bleeding per vaginum. A volume of 5 mL blood sample was taken and serum was separated using centrifugation. Triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) levels were estimated by chemiluminiscence. Results: T3, T4 and levels were comparable in all the three groups and the difference was not statistically significant. TSH levels were found to be negatively correlated with T3 and T4 values in the three groups. Only, 13% of the patients had spontaneous abortion. Nearly 6.66% of the patients in Group 1, 11.42% in Group 2 and 19.99% of patients in Group 3 ended up in abortion. TSH was found to be strongly associated with abortion in all the three groups (P ≤ 0.001). TSH levels were significantly higher in the first trimester in women who had an abortion than pregnant women who had a successful continuation of pregnancy. Conclusions: TSH was strongly associated with abortion in the first trimester in all the three groups.