The Groningen ART cohort study:the effects of ovarian hyperstimulation and the IVF laboratory procedures on neurological condition at 2 years

BACKGROUND: Up to 4% of children are born following assisted reproduction techniques (ART) yet relatively little is known on neurodevelopmental outcome of these children after 18 months of age. Only a limited number of long-term follow-up studies with adequate methodological quality have been reported. Our aim was to evaluate the effects of ovarian hyperstimulation, IVF laboratory procedures and a history of subfertility on neurological condition at 2 years.METHODS: Singletons born after controlled ovarian hyperstimulation IVF (COH-IVF, n=66), modified natural cycle IVF (MNC-IVF, n=56), natural conception in subfertile couples (Sub-NC, n=87) and in fertile couples (reference group, n=101) were assessed (using Hempel approach) by neurological examination at 2 years of age. This resulted in a neurological optimality score (NOS), a fluency score and the prevalence of minor neurological dysfunction (MND). Primary outcome was the fluency score, as fluency of movements is easily affected by subtle dysfunction of the nervous system.RESULTS: Fluency score, NOS and prevalence of MND were similar in COH-IVF, MNC-IVF and Sub-NC children. However, the fluency score (PCONCLUSIONS: Neurological condition of 2 year olds born after ART is similar to that of children of subfertile couples conceived naturally. Moreover, subfertility does not seem to be associated with a worse neurological outcome. These findings are reassuring, but we have to keep in mind that subtle neurodevelopmental disorders may emerge as children grow older.