SEARCH RESULTS FOR: Hyperthyroidism-in-Pregnancy

Hyperthyroidism in Pregnancy

Hyperthyroidism in Pregnancy: Pathogenesis and clinical findings Authors: Delaney Duchek Reviewers: GurreetBhandal,JuliaGospodinov Luiza Radu , Samuel Fineblit* * MD at time of publication ↑ Human chorionic gonadotropin (hCG) hormone stimulates TSH receptors which ↑T3/T4 & ↓ physiologic TSH production in 1st trimester & normalizes in 2nd trimester Transient hyperthyroxinemia in pregnancy (often benign) Autoantibodies ↑ stimulation of thyroid stimulating hormone (TSH) receptors Transplacental passage of TSH- receptor antibodies (can occur with normal thyroid function) Graves’ disease Transient ↓TSH & ↑T3/T4 Persistent ↓TSH & ↑T3/T4 Low birth weight Maternal congestive heart failure Pre-eclampsia (high blood pressure in pregnancy) Thyroid storm (excessive release of T3/T4 leading to a life-threatening hypermetabolic state) ↑ Triiodothyronine (T3) & thyroxine (T4) production independent of TSH Abnormal differentiation of trophoblast embryonic cells ↑ hCG levels (cells that provide nutrition to the embryo) Gestational trophoblastic disease Toxic multinodular goiter Toxic adenoma Viral infection Subacute thyroiditis (thyroid inflammation) Hyperthyroidism in Pregnancy Anterior pituitary gland releases stored TSH ↑Sympathetic nervous system stimulation ↑Thermogenesis (heat production, regulated by thyroid & variousbraincentres) ↑Hyaluronic acid in dermis & subcutis tissue of the skin (Graves’ disease specific) Transplacental passage of ↑T3/T4 to fetus Gut hypermobility Central nervous system overstimulation ↑Weight loss ↑Appetite Heat intolerance Diarrhea & ↑ bowel movements Nervousness & anxiety Hyperkinesia (excessive activity of a body part) Hyperreflexia (overactive muscle reflex response) Tremor Poor attention span ↑ Heart rate Palpitations (noticeable abnormal heartbeats) Bruit (turbulent blood flow) heard over thyroid ↓ Exercise tolerance ↑ Cardiac output De novo synthesis of TSH (synthesis of TSH independent of normal regulatory signals & processes as seen in toxic adenoma & toxic multinodular goiter) Pregnancy Complications (abnormallyhighfreeT4&thyroid stimulating antibodies in the blood impacts fetal thyroid function) ↑ Renin angiotensin aldosterone system (RAAS) activation (important regulator of electrolytes, blood volume, & systemic vascular resistance) ↑ Erythropoietin (EPO, hormone made by kidneys that stimulates red blood cell production) Pretibial myxedema (condition causing skin lesions from deposition of hyaluronic acid) Spontaneous abortion (pregnancy loss naturally ≤20 weeks gestation) Premature labour (labour ≤37 weeks gestation) Stillbirth (fetal death >20 weeks gestation) Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published September 29, 2024 on www.thecalgaryguide.com