BioNews reporting from ESHRE conference, Madrid:
Children conceived using in IVF and ICSI (intracytoplasmic sperm injection) techniques are no more likely to be affected by growth and development problems than children conceived naturally, according to a new study presented at the European Society of Human Reproduction and Embryology (ESHRE) in Madrid last week. The researchers, based at the Sahlgrenska University Hospital in Goteburg, Sweden, presented results from the biggest and longest-running study into the health of IVF children carried out so far.
The scientists looked 541 ICSI, 440 IVF children and 542 non-IVF children from Denmark, Greece, Sweden and the UK, and compared their development over five years. They found that the birth weight and height aged five of IVF and ICSI children was similar to that of non-IVF children. There were also no significant differences in verbal ability, total IQ (intelligence quotient) or behavioural problems between the three groups.
However, the researchers found a higher rate of certain malformations in ICSI children, most commonly affecting the urinary and genital systems, gut, muscles, bone or skin. The occurrence of malformations was 2.4 per cent in the non-IVF children, compared with 4.1 per cent in IVF and 6.2 per cent in ICSI children.
'We did see an increase in the malformation rate, but is this due to the technique?' asked team leader Christina Bergh. She thinks not, saying that 'the most probable explanation is selection bias towards more healthy control children'. While the IVF and ICSI children were followed from birth, many of the non-IVF children in the study were chosen from school records.
As Bergh pointed out, severely ill children tend not to go to ordinary schools, which would skew the control group towards children without health problems. But she also said that the ICSI technique, in which a single sperm is injected directly into an egg, could not be excluded as a cause of the increase. It could also be that since ICSI is used to treat men with few or poor quality sperm, genetic defects responsible for abnormal sperm production could also affect embryo development.
Bergh said that more research was needed to explain the differences in malformation rates between the three groups of children. But she stressed that: 'Overall, the results are reassuring and lay to rest fears that have been expressed about the health and welfare of children conceived through IVF and ICSI'.