(J Clin Endocrinol Metab 97: 2543–2565, 2012) بارداری و تیرویید (J Clin Endocrinol Metab 97: 2543–2565, 2012)

Effects of Hypothyroidism on Pregnancy Outcomes Maternal Fetal Anemia Hypertension Preeclampsia Abruptio placenta Postpartum hemorrhage Miscarriage Low birth weight Stillbirth Psychoneurologic impairment JCEM, 2007

Screening for Thyroid Disease in Pregnancy Although the benefits of universal screening for thyroid dysfunction may not be justified at this time, selected screening for the following should be done: Positive FHx thyroid disease Goiter TPOAb+ Symptoms Type 1 DM Miscarriage Other autoimmune disease Infertility Morbid obesity >30 years Iodine deficient area Thyroid 2011, JCEM 2012

TSH level during pregnancy 1st trimester<2.5 mIU/ml 2nd and 3rd trimester<3 mIU/ml

Graves ophthalmopathy

پرکاری تیرویید و بارداری فقط در سه ماهه اول پروپیل تیوراسیل بدهید. ید رادیو اکتیو در بارداری غیر مجاز است. در سه ماهه دوم در صورت نیاز می توانید تیروییدکتومی نمایید. با علایم بالینی TSH, T4, T3RU بیمارتان را پیگیری نمایید

اندیکاسیون های تیروییدکتومی A severe adverse reaction to ATD therapy Persistently high doses of ATD are required (over 30 mg/d of MMI or 450 mg/d of PTU); Nonadherent to ATD therapy and uncontrolled hyperthyroidism بهترین زمان جراحی 3 ماهه دوم بارداری است.

Thyrotoxicosis in pregnancy and in the post-partum period

Subclinical hyperthyroidism Treatment does not improve pregnancy outcome, and could potentially adversely affect fetal outcome

Investigation of fetal or neonatal thyroid dysfunction Measure thyroid receptor antibodies (TRAb) by 22wk gestational age in mothers with: 1) current Graves’ disease 2) a history of Graves’disease and treatment with 131I or thyroidectomy before pregnancy 3) a previous neonate with Graves’ disease 4) previously elevated TRAb.

If TRAb>2-3 Nl or women on ATD Screen maternal free T4 & fetal thyroid dysfunction and do fetal anatomy ultrasound done in the 18th-22nd week and repeated every 4–6 wk or as clinically indicated Fetal thyroid dysfunction: Thyroid enlargement, growth restriction, hydrops, advanced bone age, tachycardia, or cardiac failure.

Fetal hyperthyroidism therapy ATD with frequent clinical, laboratory, and ultrasound monitoring Umbilical blood sampling should be considered only if the diagnosis of fetal thyroid disease is not reasonably certain from the clinical and sonographic data and the information gained would change the treatment

In USA neonatal thyroid function All newborns of mothers with Graves’ disease (except those with negative TRAb and not requiring ATD) should be evaluated for thyroid dysfunction.

Gestational hyperthyroidism vs Graves’ disease Negative TRAb No goiter No need to treat with ATD Beta blockers such as metoprolol may be helpful

Post partum thyroiditis

Prevalence of PPT Prevalence rate of postpartum thyroiditis is 7.5% Brazil 13.3% Prevalence rate of postpartum thyroiditis is 7.5% NYC 8.8% Toronto 6.0% Spain 7.8% UK 16.7% Italy 8.7% India 7% Thailand 1.1% Japan 5.5% Iran 11.4% Netherlands 5.2% Denmark 3.9% Sweden 6.5% Netherlands 7.2% Denmark 3.3% 3162596-20

Autoimmune thyroid disease and miscarriage Only one randomized interventional trial has suggested a decrease in the first trimester miscarriage rate in euthyroid antibody-positive women With history of abortion: Administer T4 Elevated anti-TPO antibodies increases the risk for progression of hypothyroidism, so, screen for serum TSH abnormalities before pregnancy, as well as during the first and second trimesters of pregnancy

Thyroid nodules FNA: nodules> 1 cm 0.5 cm <Nodules< 1 cm if high-risk history or suspicious findings on ultrasound During the last weeks of pregnancy, FNA can reasonably be delayed until after delivery

Thyroid cancer If nodule on FNA is malignant or highly suspicious or exhibits rapid growth, or accompanies by pathological neck adenopathy, offer surgery in the 2nd trimester If it is papillary cancer or follicular neoplasm without evidence of advanced disease you can wait until the postpartum period for definitive surgery Administer suppresive dose of T4 Radioactive iodine (RAI) with 131I should not be given to women who are breastfeeding or for at least 4wk after nursing has ceased.

Iodine nutrition during pregnancy In the childbearing age: 150 µg/d Before and during pregnancy and breastfeeding: 250 µg/d Iodine intake should not be >500 µg/d Once-daily prenatal vitamins contain 150–200 g iodine

Changes in maternal Thyroid Function in Pregnancy  TBG  E  FT4  TSH iodine TPO Ab  HCG  TSH  FT4  goiter  Tg  TSH  TSH  placental DI III  T4 Modified from JCEM 86:2349, 2001

Thyroid & Pregnancy Physiologic changes  TBG  I requirement  urinary I excretion  T4 & T3 synthesis  HCG  immunity