Subclinical elevations of thyroid-stimulating hormone and assisted reproductive technology outcomes

The prevalence of moderately elevated TSH levels consistent with subclinical hypothyroidism (2.5-4.0 μIU/mL) was 23% in a cohort of 1,231 women pursuing assisted reproductive technologies. Preconception elevated levels of TSH were associated with diminished ovarian reserve but were not associated with adverse assisted reproductive technology or pregnancy outcomes.