Characterizing thyroid follicles histogenesis in the human fetuses: A morphological approach

Area of Science:

• Developmental biology
• Histology
• Endocrinology

Background:

• The thyroid gland, crucial for metabolism and growth, originates from the thyroglossal duct.
• Understanding fetal thyroid development is vital for diagnosing developmental thyroid disorders.

Purpose of the Study:

• To investigate the histomorphological changes in the human fetal thyroid gland during the first, second, and third trimesters.
• To establish a baseline for identifying developmental thyroid abnormalities.

Main Methods:

• A descriptive observational study using histological analysis of human fetal thyroid tissue.
• Tissue sections from stillbirths and spontaneously aborted fetuses (first, second, and third trimesters) were stained with Hematoxylin and Eosin.
• Quantitative analysis of follicular dimensions, epithelial cell characteristics, and parafollicular cell counts.

Main Results:

• Observed variations in thyroid follicle shape, vascularity, and capsule structure during development.
• Progressive increase in epithelial cell dimensions, follicle boundaries, and parafollicular cell number from the first to third trimester.
• Decrease in follicular diameter, radius, perimeter, area, and colloid volume with advancing gestation; specific changes noted in cytoplasmic and nuclear areas.

Conclusions:

• Significant histomorphological changes occur in the developing human fetal thyroid gland across trimesters.
• This baseline data aids in understanding structural and metabolic thyroid disorders during fetal development.
• Provides critical insights into normal thyroid gland morphogenesis.