Thyroid Disease During Pregnancy

Publication Date: March 1, 2017

Key Points

Key Points

  • Pregnancy has a profound impact on the thyroid gland and its function.
  • During pregnancy, the thyroid gland increases in size by 10% in iodine replete countries, but by 20%–40% in areas of iodine deficiency.
  • Production of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), increases by nearly 50%, in conjunction with a separate 50% increase in the daily iodine requirement.
  • These physiological changes happen seamlessly in healthy women, but thyroid dysfunction can occur in many pregnant women due to pathologic processes.
  • Furthermore, other thyroid illnesses such as nodular disease and thyroid cancer are occasionally detected during pregnancy, and may require treatment.

Assessment

Assessme...

...1. Testing For Thyroid Dysfunction...


Screening for Thyroid Dysfunction Before...

...regnant women should be verbally scre...

...ening to detect low free thyroxine...

...atients seeking pregnancy, or newly...

...insufficient evidence to recommen...

There is insufficient evidence to recommend for o...


...oid Function Testing and Pregnancy

...n possible, population-based trimester-s...

...of serum Free T4 measurement by the indirect anal...

...f measuring free T4, total T4 meas...


...ne Status and Nutrition...

...ry iodine concentrations can be use...

...gnant women should ingest approximately 250...

...ons, including the United States, w...

...resource countries and regions where neit...

...need to initiate iodine supplementation in pregna...

...sive doses of iodine exposure during pregn...

...odine intake from diet and dietary su...


...Auto-Antibodies & Pregnancy Complication...

...t thyroid peroxidase (TPO) or thyroglobulin (Tg) a...

...upplementation is NOT recommended for the treat...

...ravenous immunoglobulin treatment...

...nsufficient evidence to conclusively determine...

...re is insufficient evidence to recommend for...


Infertility

...fertility...

...act of Thyroid Illness upon Infertility...

...uation of serum TSH concentration is re...

...tment is recommended for infertile women wit...

...cient evidence to determine if LT4 therapy improve...

...is insufficient evidence to determine if LT4 the...

...hypothyroid women undergoing in vitro...

...ficient evidence to determine wheth...

...ticoid therapy is NOT recommended for euthyroid,...

...thyroid function testing should be performed...

...women who achieve pregnancy following contro...


Maternal Disorders

...nal Disorder...

...oidism and Pregnanc...

...of pregnancy, maternal hypothyroidism...

...ilable, population and trimester-spec...

...is not feasible, pregnancy-specific...

...nternal or transferable pregnancy-sp...

...tment of overt hypothyroidism is recommended durin...

...nant women with TSH concentrations >2.5 mU...

...nical hypothyroidism in pregnancy s...

...women with a TSH greater than the pregnancy spec...

...negative women with a TSH >10.0 mU/L. (...

...women TPO antibody negative women w...

...positive women with TSH concentrations >...

...4 therapy is NOT recommended for TPOAb-negative w...

...lated hypothyroxinemia should NOT be r...

...recommended treatment of maternal hypothyroi...

...el to the treatment of hypothyroidism...

...rt and subclinical hypothyroidism (treated or untr...

...hypothyroid women of reproductive age...

...omen treated with LT4 who are plan...

...ery, LT4 should be reduced to the p...

...ome women in whom LT4 is initiated d...

...f women with adequately treated hypothy...


...cosis in Pregnancy...

...suppressed serum TSH is detected in th...

...adionuclide scintigraphy or radioiodine up...

...e appropriate management of abnormal maternal...

...all women of childbearing age who are thyrot...

Thyrotoxic women should be rendered stably e...

...g methimazole (MMI) or prophylthiouracil...

...newly-pregnant woman with Graves’ disea...

...lowing cessation of antithyroid me...

...At each assessment, the decision to continue...

...U is recommended for the treatment o...

...nt women receiving MMI who are in need o...

When shifting from MMI to PTU, a dose ratio of...

...ATD therapy is required after 16 weeks gestatio...

...n being treated with antithyroid drugs in...

...medication during pregnancy should be admini...

...egimen of LT4 and an antithyroid drug should NO...

...n pregnancy may be indicated for uniq...

...concur with the American College of Obstetric...

...atient has a past history of Grave...

...f maternal TRAb concentration is elevated...

...If maternal TRAb is undetectable...

...If a patient is taking ATDs for treatment of Grave...

...f the patient requires treatment with A...

...f elevated TRAb is detected at weeks 18–22 or th...

...ance should be performed in women who have uncon...

...should be used in rare circumstan...

...erapy is given for hyperthyroidism caused by a...


...Advantages and Disadvantages of Therapeutic Opt...


...yroid Nodules and Thyroid Cancer During Pr...

...with suppressed serum TSH levels that persist bey...

The utility of measuring calcitonin...

...dule FNA is generally recommended for newly de...

...e scintigraphy or radioiodine uptake determi...

...regnant women with cytologically benign...

...ith cytologically indeterminate (AUS/FLUS, SF...

...egnancy, if there is clinical suspicion o...

...cular testing is NOT recommended for eva...

Papillary thyroid carcinoma (PTC) de...

...e impact of pregnancy on women with...

Pregnant women with thyroid cancer shoul...

...cy should be deferred for 6 months after a woman...

...and thyroglobulin monitoring during pregnancy...

...nd thyroglobulin monitoring should be perfor...

...sound monitoring of the maternal thyroid should...


...TA Sonographic Patterns and Estimate...


...partum Thyroiditis (PPT)

...ents with depression, including postpa...

...he thyrotoxic phase of PPT, symptomatic women...

...tithyroid drugs are NOT recommended for the tre...

...lowing the resolution of the thyrotoxic pha...

...should be considered for women with symptomatic...

...iated for PPT, discontinuation of therapy...

...ith a prior history of PPT should have TSH tes...

...eatment of euthyroid thyroid antibody-positive pr...


Fetal and Neonatal Considerations

...nd Neonatal Considerati...

...maternal thyroid illness, use of antithyroid me...


...maternal and fetal thyroid illness shou...


...uld be screened for hypothyroidism by blood spot...


...id Disease and Lactation...

As maternal hypothyroidism can adversely i...

...erse impact upon milk production and letdown,...

...t of maternal hyperthyroidism upon lactation is...

The use of 131I is contraindicated during lact...

...g treatment decisions specifically made on t...

...yroid medication is indicated for wo...

...ren of women who are treated with antithyroid dru...

...ding women should ingest approximately 250 mcg...

...ng women should supplement their di...

...dine deficient, low-resource regions, wh...

As is the case during pregnancy, sustained iod...