Thyroid function in pre-eclampsia.

Thyroid function was studied in 24 proteinuric pre-eclamptic patients and 24 gestation-matched controls. The pre-eclamptic patients had significantly lower mean total (TT4) and free thyroxine (FT4), and thyroxine-binding globulin (TBG) concentrations, and the concentration of thyroid-stimulating hormone was significantly higher. The mean total triiodothyronine (TT3) concentration, however, was similar to the controls. This is at variance with the classical low T3 syndrome reported previously for pre-eclamptic patients. Compared to the controls, 33.3% and 29.2% of the pre-eclamptic patients had low TT4 and TT3 concentrations respectively. Pre-eclamptic patients with low TT4/TT3 had significantly higher plasma urate concentrations. Thyroid hormone concentrations may reflect the severity of pre-eclampsia.