The association between type of conception through medically assisted reproduction and childhood cognition: A Danish population-wide cohort study

Previous research has found that children conceived through medically assisted reproduction (MAR) on average has cognitive outcomes on par with or above naturally conceived children. However, previous work has been unable to consider the relationship at a full population level nor consider heterogeneity across type of MAR. We use all Danish live births in the years 2006-2009 (n=259,608) with indicator for MAR conceptions (n=13,554). The dependent variable is the within-year-and-grade standardized test scores carried out in second and third grade in primary schools. We compare the test scores for spontaneously conceived (SC) children and conceived through intrauterine insemination (IUI) and assisted reproductive technologies (ART). We estimate ordinary least squares regressions with a baseline model only adjusted for birthyear and models adjusted for birth-related confounders and socio-demographic family characteristics. At baseline, ART and IUI conceived children performed better in tests than SC peers. After adjusting, ART conceived performed worse than SC peer, and IUI conceived performed as well as SC peers and better than ART conceived. Results likely reflect differences in selection of potential parents into type of MAR as well as consequences of differences in fecundability.