Thyroid Hormone Dose Adjustment in Pregnancy

Mass General Brigham

Status: Completed

Conditions: Hypothyroidism; Pregnancy

Treatments: Drug: Anticipatory dose increase of levothyroxine; Drug: levothyroxine

Study type: Interventional

Funder types: Other

Identifiers

NCT00230802

DK44128 (completed)

Details and patient eligibility

About

Our aim is to compare the safety and efficacy of 2 different empiric levothyroxine dose adjustment recommendations to be made at the first confirmation of pregnancy in women with a history of hypothyroidism. Subjects will be women with a prior diagnosis of hypothyroidism who are taking thyroid hormone replacement and who are less than 8 weeks pregnant. Upon confirmation of pregnancy, subjects will be randomized to increase their weekly thyroid hormone dose by either 2 or 3 tablets (28 or 42%). Thyroid function will be evaluated every two weeks in the first 20 weeks and then again at week 30 and post-partum. Primary endpoints will be the proportion of women in each group who remain euthyroid throughout the first trimester and throughout pregnancy.

Full description

Our aim is to compare the safety and efficacy of 2 different empiric levothyroxine dose adjustment recommendations to be made at the first confirmation of pregnancy in women with a history of hypothyroidism. Subjects will be women with a prior diagnosis of hypothyroidism who are taking thyroid hormone replacement and who are less than 8 weeks pregnant. Upon confirmation of pregnancy, subjects will be randomized to increase their weekly thyroid hormone dose by either 2 or 3 tablets (28 or 42%). Thyroid function will be evaluated every two weeks in the first 20 weeks and then again at week 30 and post-partum. Primary endpoints will be the proportion of women in each group who remain euthyroid throughout the first trimester and throughout pregnancy

Enrollment: 48 patients

Sex: Female

Volunteers: No Healthy Volunteers

Inclusion criteria

• women with a prior diagnosis of hypothyroidism, currently receiving levothyroxine therapy
• less than 8 weeks pregnant

Exclusion criteria

• cardiac disease, renal failure
• not euthyroid biochemically within 6 months pre-pregnancy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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48 participants in 2 patient groups

2 tablet increase

Active Comparator group

Description:

Patients will increase their current levothyroxine dose by 2 extra tablets per week (\~29% increase)

Treatment:

Drug: levothyroxine

Drug: levothyroxine

Drug: Anticipatory dose increase of levothyroxine

3 tablet increase

Active Comparator group

Description:

Patients will increase their levothyroxine dosage by 3 extra tablets per week (\~43%).

Treatment:

Drug: levothyroxine

Drug: levothyroxine

Drug: Anticipatory dose increase of levothyroxine