Mental development of children conceived using intracytoplasmic sperm injection. The current evidence.

There are biologically plausible reasons why children conceived using intracytoplasmic sperm injection (ICSI) may be at increased risk for delayed mental development. The first controlled study of mental development in ICSI children which was published in 1998 found 1 year old ICSI children to be at significantly increased risk for developmental delay compared with both in vitro fertilization (IVF) and naturally conceived control children. These results encouraged several groups of investigators to further study developmental outcomes for ICSI children in order to clarify the level of risk, if any. This review considers the currently available evidence from published studies which included control groups and a standardized measure of infant or child development. The 9 publications included in the review include a total of 969 ICSI children and 828 controls (343 IVF, 485 naturally conceived). All studies indicate that the majority of children conceived using ICSI have normal mental development, and most have not found ICSI children to be at increased risk for developmental delay. The evidence to date suggests that ICSI per se is not an independent risk factor for delayed child development, but that demographic factors such as level of maternal education and social class are more important determinants of developmental outcome for ICSI children.