Effect of povidone iodine on thyroid functions and urine iodine levels in caesarean operations

Objective: In the present study, the effects of povidone iodine (PI) used during Caesarean operations on maternal thyroid hormones and urine iodine levels in the infant and the mother were investigated. Design: Twenty-seven patients were allocated to the PI group I (Gr I), and 28 to the non-PI group (Group II). Maternal preoperative and 24th-h postoperative free T3 (fT3), freeT4 (fT4), TSH, and urine iodine levels were determined, as well as infant urine iodine values. Results: In both groups, fT3 levels before and after the operation were found to be reduced (p < 0.01, p = 0.01, respectively). However, the decrease in fT3 was approximately 1.5-fold higher in Gr I than in Gr II. TSH levels increased significantly in Gr I (p = 0.005). The urine iodine levels of the mothers increased 25% in Gr I, but only 2% in Gr II. Conclusions: The absorption of PI by the skin was found to lead to changes in fT3, TSH, and urine iodine excretion values in the mothers. The findings of this study of Caesarean operations, which have a short duration, might be a signal to be careful of thyroid hormone effects in operations lasting longer.