Longest-running study finds little evidence of ill-health

The biggest and longest-running study into the health of IVF children has found little evidence that fertility treatment can harm the long-term growth and development of boys and girls conceived outside the body.

The biggest and longest-running study into the health of IVF children has found little evidence that fertility treatment can harm the long-term growth and development of boys and girls conceived outside the body.

But the research has failed to give a clean bill of health to a form of treatment in whichsperm are manipulated and injected directly into the egg to increase the chances of fertilisation.

Although the study, which involved more than 1,500 children followed over a period of five years, did not find evidence to suggest that IVF was harmful, it did discover that children resulting from ICSI - intracytoplasmic sperm injection - had a much higher risk of developing malformations.

The study found that the proportion of malformations, such as heart defects or other disabilities, in ICSI children was 6.2 per cent, compared with 4.1 per cent in IVF children and 2.4 per cent in the group of children conceived naturally.

The researchers said the explanation for the increased number of malformations in ICSI children may not be due to the process itself, but to a flaw in the experimental procedure that resulted in a bias towards especially healthy children in the group of "controls" used for comparison.

These children were chosen at random from medical birth registers in Sweden and Denmark but, because such registers do not exist elsewhere, they had to be selected from mainstream schools in Britain, Belgium and Greece. Seriously ill children would be unlikely to be among the pupils at such schools.

Christina Bergh from Sahlgrenska University Hospital in Gothenburg, Sweden, said ICSI could not be excluded as the cause of malformations because the process could result in long-term damage to embryos as a result of sperm being injected into the centre of the egg.

ICSI might also increase the risk of malformations because it was frequently used on sperm from men with poor-quality semen, and these men were more likely to have a higher number of damaged chromosomes that could affect embryological development.