CHILDREN born via IVF are typically taller than those born naturally, a study has found.

It also showed that newborn IVF children, created from a fresh embryo transferred back into the mother, also tended to be about 190g lighter than naturally conceived children, The Australiansaid. 

Mark Green from the University of Auckland's Liggins Institute, who conducted the study, said up until now there had been no research conducted past the birth stage of IVF children.

"There's been four million children born from IVF ... we wanted to see what the long-term implications were," he said.

Dr Green found that IVF children conceived with fresh, as opposed to thawed, embryos, were on average up to 2.6cm taller than children born without assisted conception.

And girls were noticeably more affected by height gains than the boys.The study involved healthy, pre-pubescent children aged between four and 11, of which 72 were born from IVF using fresh embryos, 43 IVF children from frozen embryos and 94 naturally conceived children.

"We've got no real hypothesis on why that might be, we do know that a lot of different things affect males and females in utero," he said.

Dr Green has called for more research into IVF born babies because scientists do not know if the treatment is beneficial or detrimental.

"We need more long-term studies because we know some of the later diseases, such as diabetes and cardiac disease, can be affected by events that happen during gestation, and they don't really occur till the 40s or 50s," Dr Green said.