Thyroid+Disease+in+Pregnancy

Thyroid Disease in Pregnancy

Hyperthyroidism

Diagnosis

• We are not recommending universal screening for hypothyroidism in pregnancy. We do recommend checking TSH when there is any history of thyroid dysfunction or there are other autoimmune conditions such as Type I diabetes, Lupus, etc. Remember the TSH in the first trimester is normally low due to interactions with the HCG molecule.

• Check anti-TPO antibodies (order in ccLINK as anti thyroid antibodies) as part of a work-up for recurrent miscarriage and then treating with levothyroxine 50 mcg daily if they are positive (this is an arbitrary dose used in studies).

• Check TSI or TSH receptor antibodies (order in ccLINK as thyrotropin receptor antibodies 1093) Grave’s hyperthyroidism or a history of Grave’s but now hypothyroid. If the antibody level is > 3x normal the fetus should be monitored with weekly heart rates (or NSTs) and serial growth ultrasounds with evaluation for fetal goiter, due to risk of fetal hyperthyroidism. Pediatrics should be made aware of this risk.

• Patients with hypothyroidism stable on levothyroxine aiming for TSH in pregnancy less than 2.5 do not need antepartum testing.