Adrenal and thyroid function in the fetus and preterm infant.

Area of Science:

• Endocrinology
• Neonatology
• Fetal Physiology

Background:

• Adrenal and thyroid hormones regulate intrauterine homeostasis and fetal organ maturation.
• These hormones are vital for maternal-fetal communication and adaptation to extrauterine life.
• Immaturity of the hypothalamic-pituitary-adrenal axis in preterm infants can lead to vasopressor-resistant hypotension.

Purpose of the Study:

• To highlight the critical roles of fetal and perinatal adrenal and thyroid function.
• To address the challenges in diagnosing adrenal insufficiency and the controversies in thyroid hormone replacement therapy in preterm infants.
• To emphasize the need for improved understanding to guide clinical management.

Main Methods:

• Review of existing literature on fetal and perinatal adrenal and thyroid function.
• Analysis of clinical findings suggesting adrenal or thyroid dysfunction in preterm infants.
• Discussion of current diagnostic criteria and therapeutic controversies.

Main Results:

• Diagnostic criteria for adrenal insufficiency in preterm infants are often arbitrary.
• Hypothyroidism is common in extremely low gestational age infants, but treatment benefits are debated.
• Screening methods for congenital hypothyroidism and congenital adrenal hyperplasia in preterm neonates are inconclusive.

Conclusions:

• Further research into fetal and perinatal adrenal and thyroid function is essential.
• Improved understanding will enhance the management of adrenal and thyroid disorders in preterm infants.
• Addressing diagnostic and therapeutic uncertainties is critical for improving outcomes.