Influence of topical iodine-containing antiseptics used during delivery on recall rate of congenital hypothyroidism screening program.

Abstract

The proportion of newborns recalled during neonatal screening programs for congenital hypothyroidism (CH) varies substantially by country and may be higher in settings where povodine iodine (PVP-I) is used during delivery. We assessed this hypothesis by substituting PVP-I for chlorhexidine (CHL) and evaluated the reduction in the recall rate of the Irainian newborn screening program. This study investigated 2282 neonates of mothers admitted to a local hospital for delivery between December 2012 and October 2013. We measured thyorid stimulating hormone (TSH) levels in heel-prick blood specimens of infants, aged between 3 and 5 days, born to mothers who received PVP-I (phase I) and those who received CHL after withdrawal of PVP-I from obstetric procedures (phase II). Then we compared the median TSH levels and the recall rate based on a TSH level ≥5 mU/L. Of 2282 cases, 1094 infants were born to mothers exposed to PVP-I during phase I (PVP-I group) and 1188 ones were born to mothers exposed to chlorhexidine in phase II (CHL group); 6.56% of the PVP-I group and 1.91% of the CHL group were recalled later during screening (p<0.001). The median TSH level was significantly higher in the PVP-I group compared to the CHL group (1.35 vs. 1.00, p<0.001). Replacement of iodine-containing antiseptics by iodine-free ones, during delivery resulted in a significant reduction in the recall rate of the Iranian screening program for CH.