Maternal Thyroid Dysfunction and Its Association with Obstetric and Perinatal Outcomes: A Prospective Tertiary Care Study

Abstract

Background: Thyroid hormones are essential for normal maternal physiology and fetal development, and thyroid dysfunction has been associated with adverse obstetric and perinatal outcomes. Early identification of thyroid dysfunction in pregnancy is therefore clinically important, prompting this study.

Objective: To evaluate the association between maternal thyroid dysfunction and adverse obstetric and perinatal outcomes and to identify independent predictors of adverse pregnancy outcomes.

Materials and Methods: This hospital-based prospective observational study was conducted over 8 months in the Department of Obstetrics and Gynaecology of a tertiary care teaching hospital in Western Maharashtra, India. One hundred pregnant women were enrolled by consecutive sampling and followed until delivery. Thyroid function (TSH, FT3, FT4) was assessed by chemiluminescence immunoassay, with TPOAb estimated in TSH-elevated women. Analysis used chi-square/Fisher's exact test, Student's t-test/Mann-Whitney U test, and logistic regression (SPSS v28.0; p<0.05 significant).

Results: Of 100 women, 87 were euthyroid and 13 had thyroid dysfunction. Thyroid dysfunction was significantly associated with higher rates of hyperemesis gravidarum, preeclampsia, placental abruption, preterm delivery, and fetal distress. Abortion, intrauterine death, low birth weight, and neonatal jaundice occurred more frequently but were not statistically significant. TPOAb positivity was significantly associated with low birth weight. On multivariable analysis, thyroid dysfunction and TPOAb positivity remained independent predictors of adverse pregnancy outcomes, whereas age, parity, and trimester at enrolment were not.

Conclusion: Maternal thyroid dysfunction is significantly associated with adverse obstetric and perinatal outcomes, and thyroid dysfunction and TPOAb positivity independently predict such outcomes. Early antenatal thyroid screening and timely management may improve outcomes; larger multicentre prospective studies are warranted.