ESPE Abstracts (2019) 92 LB-12

Thyroid Function in Neonates Conceived After Hysterosalpingography with Iodinated Contrast Media

Nienke Van Welie1, Maite Portela1, Inez Roest2, Joukje van Rijswijk1, Harold Verhoeve3, Annemieke Hoek4, Petra Bourdrez5, Jan Peter de Bruin6, Annemiek Nap7, Mariette Goddijn8, Angelo Hooker9, Cathelijne van Heteren10, Carolien Koks2, Cornelis Lambalk1, Kim Dreyer1, Ben Willem Mol11, Martijn Finken12, Velja Mijatovic1

1Amsterdam UMC, Department of Reproductive Medicine, Amsterdam, Netherlands. 2Maxima Medical Center, Department of Obstetrics and Gynaecology, Veldhoven, Netherlands. 3OLVG, Department of Obstetrics and Gynaecology, Amsterdam, Netherlands. 4University Medical Centre Groningen, Department of Reproductive Medicine and Gynaecology, Groningen, Netherlands. 5VieCuri Medical Centre, Department of Obstetrics and Gynaecology, Venlo, Netherlands. 6Jeroen Bosch Hospital, Department of Obstetrics and Gynaecology, 's Hertogenbosch, Netherlands. 7Rijnstate Hospital, Department of Obstetrics and Gynaecology, Arnhem, Netherlands. 8Amsterdam UMC, University of Amsterdam, Centre for Reproductive Medicine, Amsterdam, Netherlands. 9Zaans Medical Centre, Department of Obstetrics and Gynaecology, Zaandam, Netherlands. 10Canisius Wilhelmina Hospital, Department of Obstetrics and Gynaecology, Nijmegen, Netherlands. 11Monash University, Department of Obstetrics and Gynaecology, Melbourne, Australia. 12Amsterdam UMC, Vrije Universiteit Amsterdam, Emma Children's Hospital, Department of Paediatric endocrinology, Amsterdam, Netherlands

Objective: Hysterosalpingography (HSG) to assess patency of the Fallopian tubes with the use of iodinated (oil- or water-based) contrast media is a standard test during fertility work-up. An observational study found an increased risk of congenital hypothyroidism in neonates whose mothers were exposed to high amounts of oil-based contrast during HSG. Oil-based contrast contains more iodine (480mg Iodine/ml) than water-based contrast (250mg Iodine/ml). We investigated whether preconceptional HSG with oil- or water-based contrast affects neonatal thyroid function.

Design: Retrospective data-analysis of an RCT (H2Oil trial) (Dreyer et al.,2017).

Materials and Methods: In the H2Oil trial, 1,119 women were randomized to receive HSG with oil-based contrast (Lipiodol®) (n=557) or water-based contrast (Telebrix Hystero®) (n=562). Of the 369 women who gave birth to a liveborn infant, 208 consented to be approached for future research. Thyroid function tests of their children were retrieved from the Dutch neonatal screening program, which includes the assessment of T4 in all newborns, followed by TSH only in those with a T4 level ≤-0.8SD score. Furthermore, amount of used contrast and time between HSG and conception were compared between the groups.

Results: Data were collected on 140 neonates conceived after HSG with oil-based (n=76) or water-based contrast (n=64). T4 SD score was -0.05 (IQR-0.5-0.5) in the oil-group versus 0.2 (IQR-0.3-0.9) in the water-group (p-value 0.12). None of the neonates had a positive screening result for congenital hypothyroidism.

The median amount of used contrast did not differ between the oil-group (9.0ml (IQR6.0-11.8)) and water-group (10.0ml (IQR7.5-14.0)) (p-value 0.43). Time between HSG and conception was comparable between the oil- and water-group (respectively, 2.3 months (IQR1.1-4.3) versus 2.1 months (IQR1.1-4.0), p-value 0.83).

There were 13 children with a T4 ≤-0.8SD score in the oil-group versus 7 in the water-group (RR, 1.5; 95%CI 0.7-3.6, p-value 0.32). All had a normal TSH value. The amount of contrast or duration between HSG and conception between neonates with a T4 ≤-0.8SD and ≥-0.8SD score in either group did not differ.

Conclusions: This study showed that preconceptional HSG with oil-based and water-based contrast did not affect thyroid function in newborns. Although our results suggest that the use of iodinated contrast for HSG is safe for the offspring, we advise to keep the amount of contrast as low as possible. Since data on maternal thyroid function was lacking, while the fetal brain relies on the mother during neurodevelopment, no inferences regarding neurodevelopment could be made.