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Updated: Apr 7, 2026
Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Association of prenatal perchlorate, thiocyanate, and nitrate exposure with neonatal size and gestational age
Kristin A Evans1, David Q Rich1, Barry Weinberger2
1Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
Background:
Perchlorate and similar anions compete with iodine for uptake into the thyroid by the sodium iodide symporter (NIS). This may restrict fetal growth via impaired thyroid hormone production.
Methods:
We collected urine samples from 107 pregnant women and used linear regression to estimate differences in newborn size and gestational age associated with increases in perchlorate, thiocyanate, nitrate, and perchlorate equivalence concentrations (PEC; measure of total NIS inhibitor exposure).
Results:
NIS inhibitor concentrations were not associated with newborn weight, length, or gestational age. Each 2.62ng/μg creatinine increase in perchlorate was associated with smaller head circumference (0.32cm; 95% CI: -0.66, 0.01), but each 3.38ng/μg increase in PEC was associated with larger head circumference (0.48cm; -0.01, 0.97).
Conclusions:
These anions may have effects on fetal development (e.g. neurocognitive) that are not reflected in gross measures. Future research should focus on other abnormalities in neonates exposed to NIS inhibitors.
