Association of TSH concentrations and thyroid autoimmunity with IVF outcome in women with TSH concentrations within normal adult range.

BACKGROUND/AIMS This study aimed to evaluate the association of thyroid-stimulating hormone (TSH) concentrations and presence of thyroid autoimmunity (TAI) with the live birth rate in euthyroid women undergoing in vitro fertilization (IVF). METHODS This study of retrospective design included 158 euthyroid women (TSH 0.5-4.5 µIU/ml) who underwent IVF from January 2006 to December 2010. Thyroid parameters were measured on day 3 of the previous nontreatment cycle. Women were subgrouped and analyzed according to their TSH concentrations (low: 0.5-2.5 vs. high: 2.6-4.5 µIU/ml) and TAI (present vs. absent). RESULTS No difference in the live birth rate was found between the TSH (low: 34.2% vs. high: 36.8%, p = 0.763) or TAI (present: 26.7% vs. absent: 34.3%, p = 0.568) subgroups. CONCLUSION This study found no evidence that increased TSH concentrations or the presence of TAI determined before IVF affect the live birth rate in euthyroid women. A better insight into the role of thyroid function during application of IVF is needed.