A large multi-cohort study has shown that adults conceived following fertility treatment have no difference in height, weight, and body fat to those who were conceived naturally.

While children conceived via IVF and ICSI were shorter, lighter and thinner than their naturally conceived counterparts, these differences were shown to disappear by the time both groups reached late adolescence.

'This is important work,' said Dr Ahmed Elhakeem, senior research associate in epidemiology at Bristol University and lead author of the paper. 'Parents and their children conceived by [assisted reproductive technologies] ART can be reassured that this might mean they are a little bit smaller and lighter from infancy to adolescence, but these differences are unlikely to have any health implications'.

The study published in JAMA Network Open aligns with previous research, which showed children conceived via IVF have increased risk of preterm birth, as well as being smaller and lighter, but which have mostly focused on the perinatal period, in the first year of the child's life.

It used data collated from 158,066 participants from Europe, Asia and Canada, aged between several weeks and 27 years. Of these 4329 had been conceived via IVF or ICSI.

'This important research is only possible through large scale international collaboration and longitudinal health studies, where participants contribute health data throughout their entire lives,' said Professor Deborah Lawlor, another author of the study, MRC Investigator and British Heart Foundation chair.

The study showed that any differences in height, weight and BMI diminished steadily as children grew older, with the difference completely diminished in adolescents aged between 14 to 17 years. A similar pattern was seen in weight, waist circumference, body fat percentage, and fat mass index showed similar results to BMI.

Since its first use in 1978 IVF has contributed to over eight million births globally.

'In the UK just over one in 30 children have been conceived by ART, so we would expect on average one child in each primary school class to have been conceived this way.' Dr Elhakeem commented.

Peter Thompson, chief executive of the Human Fertilisation and Embryology Authority added 'Around one in seven couples have difficulty conceiving in the UK which leads to around 53,000 patients a year having fertility treatment (IVF or donor insemination). The findings from this study will come as a welcome relief to these patients who begin treatment in the hope of one day having healthy children of their own'.

Sources and References

• 26 July 2022. Daily Mail
  Children conceived through IVF do NOT develop differently: Study finds difference in their height, weight and body frame disappear by late teens

• 26 July 2022. University of Bristol. 
  Concerns about effects of fertility treatment on children’s development are unwarranted, large study suggests

• 26 July 2022. Obstetrics and Gynaecology 
  Association of assisted reproductive technology with offspring growth and adiposity from infancy to early adulthood

• 27 July 2022. Independent
  Concerns about effect of fertility treatment on baby development ‘unwarranted’

Reproduced from BioNews with permission, a web- and email-based source of news, information and comment on assisted reproduction and human genetics, published by Progress Educational Trust.