[Intravenous urography in pregnancy and the risks of fetal hypothyroidism]

The authors approach the question of the risk of fetal and neonatal hypothyroidism when intravenous pyelography is carried out in the pregnant woman. They looked at a continuous series of 15 cases in 7 years, of which 8 were studied retrospectively and 7 prospectively. They did not find any clinical or biological signs of hypothyroidism when the children were from 10 months to 9 years of age at review. The authors approached the reaction of the fetal thyroid to this excess dose of iodine considering what is known about the physiology of this gland in utero and the publications concerning hypothyroidism occurring after prolonged administration of iodine or amniofetography. They conclude that there is probably a temporary disturbance of fetal thyroid function but it does not continue into the neonatal period. All the same, caution is advocated because intravenous urography during pregnancy should be carried out only for very tight indications and the newborn should be carefully examined.