Thyroid Ontogenesis 0 8th gestational weeks: synthesis of thyroglobulin 0 10 12th gestational weeks: pitutary gland begins to secrete TSh, thyroid gland synthesis of T3, T4 30th gestational weeks: hypothalamic pitutary-thyroid axis is functioning and independent of the maternal axis⚫ 8th gestational weeks: synthesis of thyroglobulin ⚫ 10~12th gestational weeks: pitutary gland begins to secrete TSH,thyroid gland synthesis of T3、T4 ⚫ 30th gestational weeks: hypothalamic￾pitutary-thyroid axis is functioning and independent of the maternal axis Thyroid Ontogenesis