van Welie N, Roest I, Portela M, et al. - Researchers examined if neonatal thyroid function is affected by exposure to preconceptional hysterosalpingography (HSG) with iodinated oil-based contrast vs iodinated water-based contrast. In this retrospective study, they analyzed data from 214 women who had an ongoing pregnancy within 6 months leading to a live birth after an HSG with oil-based contrast compared to 155 women after HSG with water-based contrast. Among these 369 women with a live born infant, 138 provided informed consent to collect data on the thyroid function tests of their offspring (n = 140). The oil group had median T4 concentration of 87.0 nmol/l vs 90.0 nmol/l in the water group. A positive screening result for CH was not evident in any of the neonates. Per outcomes, there was no influence of preconceptional HSG with iodinated contrast on the neonatal thyroid function.