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Male Infertility from Cellphones
Men who use mobile phones could be risking their fertility, warn
researchers. A new study shows a worrying link between poor sperm and
the number of hours a day that a man uses his mobile phone. Those who
made calls on a mobile phone for more than four hours a day had the
worst sperm counts and the poorest quality sperm, according to results
released yet at the American Society for Reproductive Medicine annual
meeting in New Orleans (23rd October 2006).
Doctors believe the damage could be caused by the electromagnetic
radiation emitted by handsets or the heat they generate. The findings
suggest millions of men may encounter difficulties in fathering a
child due to the widespread use of mobile phones and offers another
possible explanation for plummeting fertility levels among British
males.
Sperm counts among British men have fallen by 29% over the past
decade, a drop which has also been blamed on increasing obesity,
smoking, stress, pollution and 'gender-bending' chemicals which
disrupt the hormone system. The latest study backs up previous
research which indicated a link between mobile phone use and sperm
quality, but it is the biggest and best designed to date.
US
researchers in Cleveland and New Orleans, and doctors in Mumbai,
India, looked at more than 360 men undergoing checks at a fertility
clinic who were classified into three groups according to their sperm
count. Men who used a mobile for more than four hours a day had a 25%
lower sperm count than men who never used a mobile. The men with
highest usage also had greater problems with sperm quality, with the
swimming ability of sperm - a crucial factor in conception - down by a
third. They had a 50% drop in the number of properly formed sperm,
with just one-fifth looking normal under a microscope.
Professor Ashok Agarwal, director of the Reproductive Research Centre
at the Cleveland Clinic, Ohio, who led the study, said "Almost a
billion people are using cell phones around the world and the number
is growing in many countries at 20-30% a year.
"In another five years the number is going to double. People use
mobile phones without thinking twice what the consequences may be.
"It is just like using a toothbrush but mobiles could be having a
devastating effect on fertility. It still has to be proved but it
could have a huge impact because mobiles are so much part of our
lives." Altogether 361 men in the study were divided into four
groups, with 40 never using a mobile, 107 men using them for less than
two hours a day, 100 men using them for two-four hours daily and 114
making calls for four or more hours a day.
The main finding was that on four measures of sperm potency - count,
motility, viability and morphology, or appearance - there were
significant differences between the groups. The greater the use of
mobile phones, the greater the reduction in each measure. Prof Agarwal
said "This was very clear and very significant. Many in the lowest
group for sperm count would be below normal as defined by the World
Health Organisation."
The WHO says a normal sperm count is above 20 million per millilitre
of seminal fluid. "There was a significant decrease in the most
important measures of sperm health with cell phone use and that should
definitely be reflected in a decrease in fertility" he said. Motility
measures the swimming ability of sperm, viability measures whether
non-swimming sperm are still alive while morphology is the appearance
compared to the norm. Although the men were seeking fertility
treatment at a clinic in Mumbai, not all would have had a problem - it
could be their partners, he added.
Prof Agarwal said the most likely mechanism was damage to sperm-making
cells in the testes caused by electromagnetic radiation or heat,
although a fall in hormone production could also affect sperm motility
and sperm DNA. He said: "These cells in the testes have been shown to
be susceptible to electromagnetic waves in previous research in
animals. "Somehow electromagnetic waves may be causing direct damage
to these cells and that perhaps causes a decrease in sperm
production."
Mobiles may also increase temperature in the groin, if a man was
wearing it on a belt or carrying it around in a pocket. Prof Agarwal
said it was too early to advise men trying to start a family about
whether they should limit their mobile phone use. He said "We still
have a long way to go to prove this but we have just had another study
approved."
More than 40 million people in Britain are thought to use mobile
phones. Alasdair Philips, director of the consumer pressure group
Powerwatch said "It's a plausible link between the amount of time
spent using a mobile phone and a possible effect on male fertility.
"The eyes, breasts and testicles are the areas of the body most likely
to absorb the energy and many men carry their mobiles attached to
their belt."
Sending text messages uses less power than talking but it can be a
more intense emission of radiation, especially on trains, he said.
"I've seen men on trains spending two or three hours continually
texting with their mobile phones held in their laps, and they press
Send in the same position when it starts to seek a signal. "This
needs a considerable amount of power within what is effectively a
metal box. We advise people to send a text with their arm outstretched
next to the window when travelling on a train" he added. He said
local heating of the groin triggered by a mobile phone might also be
involved in affecting sperm quality.
"Sperm is very temperature sensitive as shown by many studies, and a
short-term rise in temperature could be responsible" he added.
However, Dr Allan Pacey, senior lecturer in andrology at the
University of Sheffield, said "This is a good quality study but I
don’t think it tackles the issue. "If you’re using your phone for four
hours a day, presumably it is out of your pocket for longer. That
raises a big question: how is it that testicular damage is supposed to
occur?" He said mobile phone use may be a marker for other lifestyle
factors known to affect sperm quality.
"Maybe people who use a phone for four hours a day spend more time
sitting in cars, which could mean there’s a heat issue. It could be
they are more stressed, or more sedentary and sit about eating junk
food getting fat. Those seem to be better explanations than a phone
causing the damage at such a great distance" he added.
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