• Suwarna M. Nanne
• Punam V. Chikankar
• Dhanshree S. Nibrad
• Dr. Nilesh O. Chachda

The two primary thyroid hormones, thyroxine (T4) and triiodothyronine (T3), are essential in growth, metabolism as well as neurodevelopment. Their influence extends from early embryonic life through adulthood, impacting nearly all organ systems. Maternal thyroid activity is particularly vital during pregnancy, since the foetus depends on maternal T4 during early gestation for optimal brain maturation and neuronal differentiation. Hypothyroidism, characterized by inadequate thyroid hormone production, remains a common endocrine condition, particularly among women of reproductive age. Even subclinical Unhealthy thyroid function has been connected to adverse consequences for the mother and the fetus during pregnancy, such as miscarriage, premature birth, birth defects, and delayed neurocognitive development in the progeny. This review consolidates current knowledge regarding thyroid hormone physiology, mechanisms of action, and the pathophysiological implications of hypothyroidism, emphasizing maternal and fetal interdependence. Furthermore, it explores the relationship between hypothyroidism and neurodevelopmental and neurological disorders such autism spectrum disorder (ASD), Parkinson's disease, and Alzheimer's disease, elucidating the possible mechanisms linking thyroid dysfunction with altered brain development and function. Congenital hypothyroidism (CH) is one of the primary preventable causes of intellectual impairment, underscores the necessity for early detection and intervention through neonatal screening programs and maternal thyroid assessment. The review also highlights the healing significance of levothyroxine (L-T4) as the therapy of choice for hypothyroidism during pregnancy, ensuring adequate fetal neurodevelopment. Universal screening strategies for thyroid dysfunction remain an area of ongoing debate; however, the evidence strongly supports targeted screening and timely management to mitigate long-term neurodevelopmental deficits. Overall, understanding thyroid-related hormones dynamics during pregnancy and early life is critical for optimizing maternal health and preventing lifelong neurocognitive impairment in offspring.

Thyroid hormone, Hypothyroidism, Maternal, Neurosensory disorder, congenital hypothyroidism

"Review on effect of maternal hypothyroidism on fetal development and neurodegenerative disease", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 11, page no.d333-d343, November-2025, Available :http://www.jetir.org/papers/JETIR2511337.pdf

"Review on effect of maternal hypothyroidism on fetal development and neurodegenerative disease", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 11, page no. ppd333-d343, November-2025, Available at : http://www.jetir.org/papers/JETIR2511337.pdf