Intellectual Disability in Children Conceived Using Assisted Reproductive Technology.

OBJECTIVES

To examine whether children conceived using assisted reproductive technology (ART) have a higher risk of intellectual disability (ID) compared with non-ART-conceived children and describe known causes of ID in these groups.

METHODS

We linked ID and ART data from population-based registers in Western Australia. Our cohort included live births from 1994 to 2002 (n = 210 627) with at least 8 years of follow-up. The prevalence of ID was compared between ART- and non-ART-conceived children, and risk of ID was estimated using Poisson regression with robust SEs. We also stratified by plurality and gestation at delivery.

RESULTS

Children conceived using ART had a small increased risk of ID (risk ratio 1.58; 95% confidence interval 1.19-2.11) even when analyses were restricted to singleton births (risk ratio 1.56; 95% confidence interval 1.10-2.21). The risk of ID was more than doubled for those born very preterm, for severe ID, and after intracytoplasmic sperm injection (ICSI) treatments. Children conceived using ICSI had a greater risk of ID than those conceived using in vitro fertilization and were more likely to have a known genetic cause for ID (27.6% vs 12.9% in vitro fertilization and 11.9% non-ART).

CONCLUSIONS

The risk of ID was increased in children born after ART in Western Australia from 1994 to 2002. More recent cohorts should be examined to assess the impact of important changes in ART clinical practice. Our results are particularly pertinent because multiple embryo transfers are routinely performed in many countries, increasing the risk of preterm birth, and ICSI use rates are high.