Thyroid Disorders in Pregnancy Flashcards
case 2 has evident hyperthyroidism, but TSH is pretty low in the case 1 as well, indicating that it might have a subclinical picture
clinical features of hyperthyroidism common to pregnancy
- heat intolerance
- tachycardia
- wide pulse pressure
- flow murmur
- radiant heat from hands
- goiter– in iodine deficient areas
Changes in thyroid physilogy in pregnancy:
- HCG stimulates ___ receptor
- HCG peaks at end of ___ trimester
- 20% of pregnant women have TSH below nonppregnant TSH reference range from 8-14 weeks gestation, but free T4 and T3 is normal.
- HCG stimulates TSH receptor
- HCG peaks at end of 1st trimester
- 20% of pregnant women TSH below nonppregnant TSH reference range from 8-14 weeks gestation, but free T4 and T3 is normal.
how does TSH level and free T4 levels change during pregnancy
TSH: first trimester: reduced TSH at 7-14 weeks), then it rreturns to baseline in third trimester.
- free T4 decreases is in the second and third trimesters
3) 20% pregnant women TSH below nonpregnant TSH
reference range from 8-14 wks gestation but Free T4 and
Free T3 normal
outline how TSH levels normal range change depending on gestational weeks
in pregnancy, thyroid binding globulin concentration ____. Why?
increases by 2-3 times. Estrogens stimulate expression of TBG in liver, and the normal rise in estrogen during pregnancy induces roughly a doubling in serum TBG concentratrations.
General outline when first thinking about thyroid issues in pregnancy
- check for goiter
- use gestational age specific TSH reference range
- look at free Y4 and T3
- clinical follow up and repeat TSH 4 weeks later.
most common etiology of hyperthyroidism in pregnancy
85-90% of casese of hyperthyroidism in pregnancy is Graves disease
- other etiologies include toxic MN goiter, subacute thyroiditis, toxic adenoma, gestational trophoblastic disease
causes of Transient Hyperthyroxinemia of Pregnancy
hyperthyroidism and pregnancy general diagnosis
decreased TSH
increased free T4, free t3,
goiter
5 risks of untreated hyperthyroidism in pregnancy
- miscarriage
- preterm delivery
- lpw bith weight
- pre-exlampsia
- thyroid storm
T/f the first step of manageing hyperthyroidism in pregnancy is radioiodine
false. radioiodine is contraindicated
Which antithyroid medication is preferred to use in hypertension of pregnancy? compare the two most common classes
Propylthiouracil (PTU) preferred over Methimazole (<16
weeks gestation)
outline the birthdefects seen in the use of methimazole anti-thyroid meds (Methimazole Embryopathy)
choanal atresia common
general management of hyperthyroidism in pregnancy if you can’t use radioiodine
4) Render pt euthyroid with low dose antithyroid
medication (PTU preferred until 16 wks gestation)
•
5) Monitor TSH, Free T4 every 1 to 4 wks to titrate
antithyroid medication
• 6)Keep Maternal freeT4 high trimester specific normal
note
t/f anti-thyroid drugs are safe for breastfeeding
true
true false: radioiodine remains contraindicated of breasfeeding
true