Abstract
Objective To evaluate subsequent pregnancy outcomes in women previously identified during an
index pregnancy to have subclinical hypothyroidism (SCH).
Study Design From 2000 to 2003, thyroid analytes were measured in 17,298 women. Using their index
pregnancy thyroid-analyte classification, pregnancy outcomes were compared between
the returning cohorts.
Results There were 6,985 women previously screened and subsequently delivered at our hospital
though 2011 with 230 (3.3%) designated to have SCH and 6,645 (95.1%) euthyroid. Significant
differences between the two cohorts included risk for diabetes (odds ratio [OR] 1.8,
95% confidence interval [CI] 1.2 to 2.7, p = 0.005), gestational diabetes (OR 1.74, 95% CI 1.13 to 2.69, p = 0.015), and stillbirth (OR 3.5, 95% CI 1.05 to 11.68, p = 0.042). After adjustment, the increased likelihood of diabetes (adjusted OR 1.58,
95% CI 1.04 to 2.40, p = 0.032) and stillbirth (adjusted OR 3.41, 95% CI 1.01 to 11.49, p = 0.048) persisted.
Conclusions Women identified during a previous pregnancy with SCH are at increased risk for some
adverse perinatal outcomes during a subsequent pregnancy.
Keywords
subclinical hypothyroidism - diabetes - stillbirth