Iodine Status, Thyroid Disorder and Feto-Maternal Outcome among the Tribal Pregnant Women of Eastern Himalayas

Abstract

Introduction: Iodine deficiency and thyroid disorder during pregnancy have adverse effects on fetal and neonatal outcomes. Objective: To assess iodine status and thyroid functioning during pregnancy and to evaluate the feto-maternal outcome. Methods: Urinary iodine content (UIC) is determined by arsenic cerium catalytic spectrophotometry method and thyroid hormone analysis was carried out by chemiluminescence assay. Fetal and neonatal outcomes were obtained from hospital records. Results: Among the considered tribal pregnant women 56.75% had insufficient urinary iodine and 24.5% had a thyroid disorder. Thyroid disorder was more common in pregnant women with urinary iodine concentration (UIC) <99 μg/L than UIC >150 μg/L (56.75% vs 41.5%). Pregnant women with UIC<99 μg/L had a higher incidence of anemia (86.36%), gestational diabetes mellitus (GDM) (3.33%), and preeclampsia (5.71%) than UIC >150 μg/L. The fetal outcome with UIC <99 μg/L had a higher incidence of low birth weight (9.09%) and preterm births (1.9%). Stillbirths were distributed equally among different UIC groups. The neonatal outcomes with UIC <99 μg/L between 150-249 μg/L had a higher incidence of respiratory distress (5.23%). Hypothermia was equally distributed among different UIC groups. Subclinical hypothyroid had a high prevalence of anemia (62.96%), preeclampsia (3.7%), and GDM (6.17%) respectively than the euthyroid group. The fetal outcome with low birth weight (LBW) (9.87%), stillbirths (3.7%), and preterm birth (8.64%) was more common in the subclinical hypothyroid than in the euthyroid group. Among the neonatal outcomes respiratory distress (6.17%) and hypothermia (4.93%) were more common in subclinical hypothyroid than euthyroid pregnant women. Conclusion: Insufficient maternal iodine and thyroid disorders during pregnancy were associated with adverse pregnancy outcomes.