Academic performance in adolescents aged 15–16 years born after frozen embryo transfer compared with fresh embryo transfer: a nationwide registry‐based cohort study

Abstract

Objective To assess academic performance in singletons aged 15–16 years conceived after frozen embryo transfer (FET) compared with singletons born after fresh embryo transfer (ET) in Danish cohorts born from 1995 to 2001. Design Danish national registry‐based cohort study. Setting Danish national registries. Population All 6495 singletons conceived after assisted reproductive technology (ART) treatment in Denmark from 1995 to 2001 [FET (n) = 423; fresh ET (n) = 6072]. Methods Mean test scores on a national standardised and international comparable grading‐scale. Comparisons of test score were first made in univariate analysis (Model 1) and secondly in a multivariate linear model (Model 2) adjusting for relevant reproductive and socio‐demographic covariates such as the occupational and educational level of the parents. Sensitivity analyses on FET‐IVF (in vitro fertilisation) versus fresh ET‐IVF and FET‐ICSI (intracytoplasmic sperm injection) versus fresh ET‐ICSI were made. Linear mixed models were used to account for the correlation in test scores of siblings for continuous outcome. Main outcome measures Mean overall test score and test score in Danish, mathematics, English, and physics/chemistry. Results Crude and adjusted mean test scores were similar for adolescents conceived after FET compared with fresh ET. The crude mean difference was +0.11 (95% CI −0.11; 0.34), and the adjusted mean difference was +0.12 (95% CI −0.09; 0.34). Conclusions Adolescents conceived after FET had similar academic performance at 15–16 of years of age compared with children conceived after fresh ET. Tweetable abstract Using frozen embryos in fertility treatment does not affect school performance in Danish adolescents aged 15–16 years.

The health of children conceived by ART: ‘the chicken or the egg?’

“…No difference was found in the adjusted analysis for twins (Spangmose et al 2017) Similar results were found in a large population-based Swedish study of 8,323 ART singletons (Norrman et al 2018). The effect of FET versus fresh ET on the school performance of children was reported in a recent Danish study from the same group and no differences were observed (Spangmose et al 2018).…”

Fetal neurosonography and infant neurobehavior following conception by assisted reproductive technology with fresh or frozen embryo transfer

“…Interestingly, our findings were more pronounced in the fresh ET than in the frozen ET group, contrary to a registry‐based study reporting a statistically higher risk of neurodevelopmental delay associated with ART (particularly ICSI using ejaculated sperm with fresh and frozen ET), with higher risk for ICSI with frozen ET, when restricting the analysis to singletons 8 . Nevertheless, no differences were reported between fresh and frozen ET when comparing academic performance in adolescents, in an uncontrolled follow‐up study, in which, however, mild conditions may have been underrepresented 68 . A birth cohort study with a 2‐year follow‐up reported reassuring results for ART, but it was underpowered to detect differences between the fresh and frozen ET modalities 69 .…”

Long-term health of children conceived after assisted reproductive technology

“…However, after adjustment for relevant confounders, results were similar in the two groups. Comparisons have also been made between children from IVF and ICSI and between children from fresh and frozen cycles (10)(11)(12), with similar results.…”