Association between thyroid hormone levels and 4,4′-DDE concentrations in pregnant women (Valencia, Spain)

Serum concentrations of 4,4′-DDE were associated with increased TSH and reduced FT4 but not TT3 levels. Our results suggest that some environmental chemicals may interfere with the thyroid system of pregnant women. The major role that maternal THs may play in fetal neurodevelopment makes these findings especially relevant.