Can thyroid dysfunction in mothers influence neonatal thyroid profile?

Abstract

Thyroid hormones play a critical role in normal CNS maturation. Fetus is entirely dependent on maternal thyroid hormone before the onset of endogenous thyroid hormone production. Maternal hypothyroidism alone during early gestation can lead to mild but significant cognitive impairment of the offspring.  Infants of mothers with thyroid problem are more likely to have elevated TSH during newborn screening. Aim of the Study: The study was done to know whether maternal thyroid dysfunction can influence neonatal thyroid profile. Materials and Methods: This was a prospective cohort study in which 171 neonates who satisfied the inclusion criteria  were serially enrolled during the study period. Of the 171 neonates enrolled,70 neonates were born to mothers with thyroid dysfunction  and 101 neonates  were born to normal mothers.TSH estimation was done in all enrolled neonates at 72 hrs  and result interpreted using AAP guidelines. Results: Out of 171 neonates, 155 babies (91%)had a TSH value of < 10 mIU/L ,14(8%) had TSH between 10  and 40 mIU/L and  2 babies (1%) had  TSH > 40 mIU/L . All the neonates who had TSH > 40 mIU/L were born to mothers with thyroid dysfunction.  Neonates who had TSH > 40mIU/L were all females where as there was a male predominance in the group who had TSH between 10 and 40 mIU/L. Conclusion It may be concluded that maternal thyroid hormones play a crucial role in the thyroid function status of newborns and their early neurodevelopment.