Background: In vitro fertilisation (IVF) has been widely used during the last decades. Increased susceptibility to birth defects and a higher cardiometabolic risk in children born after IVF than naturally conceived (NC) children have been reported. Also, a higher incidence of hyperthyrotropinemia has been noted in children born after IVF with respect to NC children and has been attributed to an epigenetic modification of the TSH set-point.
Objective and hypotheses: To retrospectively evaluate the main characteristics and outcome of children born after IVF and diagnosed with CH.
Method: Data from the medical records of children diagnosed with CH by the Greek national screening program were reviewed.
Results: A total of 1 051 children with CH were analyzed. Of these, 152 neonates (14.5%) were born following IVF (88 boys and 64 girls; ratio 1.4:1). 89.5% of neonates born after IVF were premature (<37 gestational week) and 79.5% had a birthweight below 2500 g With respect to TSH values at diagnosis, 10% had a TSH >20 mIU/ml, 11% between 10 and 20 mIU/ml and 79% between 6 and 10 miU/ml. With respect to thyroid ultrasonography, only 4% had absence of or a very small thyroid gland. Pertinent longterm data were available in 62 boys and 48 girls. With respect to the outcome, LT4 substitution therapy was discontinued only in 50% of boys and 37% of girls.
Conclusion: Children born after IVF constitute a relatively large subgroup of children with CH, with a notable male predominance. Anatomical thyroid defects are rare. Although hypothyroidism at diagnosis is mild based on TSH values, in 50% of boys and 63% of girls born after IVF, a certain degree of dysfunction of the Hypothalamic-Pituitary-Thyroid-axis seems to persist. The reason of the gender dimorphism is not apparent.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology