Document Detail

The relationship of preconception thyrotropin levels to requirements for increasing the levothyroxine dose during pregnancy in women with primary hypothyroidism.
MedLine Citation:
PMID:  20860419     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Most women with hypothyroidism require an increase in their dose of levothyroxine (LT4) after conception. To minimize fetal and maternal complications of maternal hypothyroidism, it is thought that women should be rapidly restored to the euthyroid state. The objectives of this study was to determine the percentage of hypothyroid women who would need to increase their dose of LT4 dose even if they had a preconception (pre-C) serum thyrotropin (TSH) of <2.5 mIU/L as recommended by the Endocrine Society's guidelines and to ascertain whether there was a relationship between the pre-C TSH value and the need to increase the LT4 dose during pregnancy.
METHODS: Fifty-three pregnant women with hypothyroidism on LT4 treatment in whom the pre-C serum TSH was <2.5 mIU/L, but which was within the normal range, within the 6 months before pregnancy were retrospectively studied. An additional selection criterion was that their LT4 dose at the time of their first prenatal visit was the same as that received pre-C.
RESULTS: Seventeen patients had to increase their LT4 dose during pregnancy, because their serum TSH was increased at the time of the first prenatal visit (Group 1); and 36 patients did not have to increase their dose of LT4 during pregnancy (Group 2). The pre-C TSH was significantly higher in Group 1 (1.55 ± 0.62 mIU/L) than in Group 2 (0.98 ± 0.67 mIU/L). When pre-C TSH range was 1.2-2.4 mIU/L, 50% of the patients required an increase in the LT4 dose during pregnancy. In contrast, when the pre-C TSH was <1.2 mIU/L, only 17.2% (p< 0.02) had to increase the LT4 dose during pregnancy.
CONCLUSIONS: We suggest that in women with hypothyroidism who are planning to become pregnant, serum TSH levels should be in the normal range but should not be greater than about 1.2 mIU/mL.
Marcos Abalovich; Graciela Alcaraz; Jessica Kleiman-Rubinsztein; María Magdalena Pavlove; Cecilia Cornelio; Oscar Levalle; Silvia Gutierrez
Related Documents :
10920109 - Analysis of mid-trimester corticotrophin-releasing hormone and alpha-fetoprotein concen...
10214609 - Pre-eclampsia disrupts the normal relationship between serum leptin concentrations and ...
12473869 - Skin capillary density changes in normal pregnancy and pre-eclampsia.
3673639 - The maternity blues: exploration of a psychological hypothesis.
10189019 - Impaired antioxidant activity in women with pre-eclampsia.
18992679 - Soluble and membranous vascular endothelial growth factor receptor-1 in pregnancies com...
24602549 - Multiple extrauterine pregnancy with early and near full-term mummified fetuses in a ne...
3954449 - Pregnancy and delivery after cone biopsy of the cervix.
17220949 - Localization of chorionic pregnancy-associated glycoprotein family in the pig.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Thyroid : official journal of the American Thyroid Association     Volume:  20     ISSN:  1557-9077     ISO Abbreviation:  Thyroid     Publication Date:  2010 Oct 
Date Detail:
Created Date:  2010-10-04     Completed Date:  2011-01-20     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9104317     Medline TA:  Thyroid     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1175-8     Citation Subset:  IM    
Endocrinology Division, Hospital Carlos Durand, Diaz Velez 5044, Buenos Aires, Argentina.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Hypothyroidism / blood,  drug therapy*
Pregnancy Complications / blood*,  drug therapy*
Retrospective Studies
Thyrotropin / blood*
Thyroxine / administration & dosage,  therapeutic use*
Reg. No./Substance:
7488-70-2/Thyroxine; 9002-71-5/Thyrotropin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Outcomes of children and adolescents with well-differentiated thyroid carcinoma and pulmonary metast...
Next Document:  Dietary iodine restriction in preparation for radioactive iodine treatment or scanning in well-diffe...