Figures released by the UK's Human Fertilisation and Embryology
Authority (HFEA) reveal the number of IVF cycles performed each year has continued
to rise while the overall multiple pregnancy and birth rate has declined.
Meanwhile, figures from the Office
for National Statistics (ONS) show that the overall number of babies born
in England and Wales has increased by more than a fifth in the past decade and
the multiple birth rate in the general population has increased.
The HFEA reports that in 2011 48,147 women received 61,726 cycles of IVF or ICSI, around four percent
more cycles than in 2010. The overall live birth rate per cycle has remained
steady at around 24 percent between 2009 and 2010, with a long term increase
from 14 percent in 1991 to 24.5 percent in 2010.
It also said that in 2011 six out of ten IVF cycles were
funded privately, with no perceived change since 2010. Around three percent of
women who had IVF or ICSI did so as part of an egg sharing agreement or to produce
eggs or embryos for donation.
The
ONS reports that with the exception of a small fall in 2009, births have been
increasing every year since 2001. There were 723,913 live births in 2011, rising
from 594,634 in 2001. According to the ONS, just over 16 in every 1,000
deliveries in 2011 were multiple births, compared to a rate of 14.8 a decade
earlier.
Women aged 45 and over had the highest multiple pregnancy rate
with an almost one in ten chance of giving birth to twins or triplets. In 2011, 11,330 women gave birth to twins and just three to quads or
more.
The HFEA figures show that the overall multiple pregnancy
rate following fertility treatment fell from 26.6 percent in 2008 to 20.1
percent in 2011, however. The greatest decrease was seen in women aged between
18 and 34 who accounted for the greatest increase in elective single embryo
transfer.
Fertility treatment is far more likely to result in multiple
births than natural conception. On average, around a
quarter of IVF pregnancies result in multiple births compared to one
percent among women who conceive naturally. Around 1.5 percent of all births in the UK
each year are from IVF or ICSI.
As part of a national strategy to reduce the multiple
birth rate, the HFEA adopted a policy to allow clinics to establish their own
strategies to promote single embryo transfer for those considered to have the
highest chances of conceiving, even when more are available. The HFEA also sets
a maximum multiple birth rate for clinics, currently set at ten percent.
Explaining
the rise in multiple births in the ONS figures, Dr
Yacoub Khalaf, a consultant gynaecologist at the Assisted Conception Unit
of Guy's and St Thomas' Hospital in London, told
the Telegraph: 'It has long been recognised that most multiple pregnancies
are from non-IVF treatment, which is mostly the use of stimulation drugs'.
'GPs
and hospital consultants are prescribing these drugs and they can be quite
generous. Doctors in the community can just give the drugs and hope for the
best. If the process is not monitored rigorously enough you can end up with
what we are observing here with these figures', Dr Khalaf explained.
He also said that increasing numbers of older mothers conceiving
naturally and couples travelling abroad to receive unregulated fertility
treatment may account for the rise in multiple pregnancies.
For women, multiple pregnancy carries an increased risk of
miscarriage and pre-eclampsia, among
other complications. In addition,
half of all twins are born prematurely and are more likely to have cerebral
palsy than single babies.
The HFEA collects data from clinics in England, Wales,
Scotland and Northern Ireland. The ONS data is compiled for births in England
and Wales only and will include births in these regions from fertility treatment presented
by the HFEA.
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