'In Vitro Fertilization' Kids May Be Taller
Small Study Shows Height and Cholesterol Differences in Kids Conceived Through IVF
June 7, 2005 -- In a new study, children conceived through in vitro
fertilization (IVF) tended to be taller and have better cholesterol than their
peers who were conceived naturally.
The study, conducted in New Zealand, wasn't large, so it's not the final
word on those traits. The study compared 50 children conceived through IVF with
60 naturally conceived children. All of the kids were healthy and were born
without a twin or other multiples.
The results were presented in San Diego at The Endocrine Society's annual
meeting. Researchers included Harriet Miles, MD, of the University of
IVF Is 27 Years Old
It's been nearly 27 years since the first IVF baby, England's Louise Brown,
was born. Since then, millions of babies have been conceived through
reproductive technologies such as IVF.
However, there hasn't yet been much long-term research on children conceived
through IVF, say Miles and colleagues. Almost two years ago, European experts
reported that in the longest-running study to date, babies conceived through
IVF and intracytoplasmic sperm injection (ICSI)
didn't face more health problems than
naturally conceived babies. That study included 440 babies born through
Miles and colleagues studied children who were 6 or 7 years old. A host of
measurements were done, including height, bone scans, and blood tests. The
researchers took into account parental height and weight.
The children conceived through IVF tended to have been born about a week
earlier and at a slightly lower birth weight than their peers. They were also
taller than the naturally conceived children, with the IVF girls taller than
the IVF boys. However, none had hit puberty yet.
The IVF group also had a better blood fat profile. They had higher levels of
HDL "good" cholesterol, lower triglyceride levels, and a trend toward
lower LDL "bad" cholesterol levels, say the researchers.
No significant differences were reported in fasting insulin levels or body
It could be that IVF technologies altered genes related to growth and fat
regulation, says the study.