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A potential cure for male infertility has been discovered by scientists. In a major breakthrough, researchers have for the first time succeeded in using artificially-grown sperm to fertilise eggs.(Left Photo:Seven baby mice were born under the ground-breaking process)
The technique could lead to a cure for some types of infertility - by allowing men to 'grow' their own sperm.
However, critics say the technique, which is the brainchild of a Newcastle University scientist, could lead to men being made redundant from the process of creating life.
They also caution that any treatment is still years away from use in hospitals and clinics. The technique centres around stem cells - blank cells which have the power to turn into other cell types, creating a 'repair kit' for the body.
Biologist Karim Nayernia (CORR) succeeded in removing the cells from mouse embryos and coaxing them into developing into sperm. The sperm was then used to fertilise eggs which were transplanted into female mice and seven baby mice were born.
While other scientists have succeeded in growing sperm in the lab, this is the first time artificially-grown sperm has been used to create new life.
Growth problems
Although most of the mice lived to adulthood, the animals were far from healthy, suffering from conditions ranging from breathing difficulties to growth problems.
Despite this, Prof Nayernia, who has just joined Newcastle University's stem cell research team, believes his work offers fresh hope for the 1.5million British men blighted by infertility. It could shed new light on the production of sperm in the body - or spermatogenesis - and even be used to boost the production of sperm in infertile men, including those left sterile by treatment for cancer.
The professor, who carried out the research while at Georg-August University in Gottingen, Germany, said: "This research is particularly important in helping us understand more about spermatogenesis, the biological process in which sperm in produced. We must know this if we are to get to the root of infertility.
"This knowledge could be translated into treatments for men whose sperm is dysfunctional, although this several years down the line."
The treatments - which are at least five years away - could include removing immature sperm cells from a man's testicles, growing them into fully-functional sperm in the lab, and then putting them back in the man's body.
Alternatively, identification of a common flaw in the sperm-making process could lead to the creation of a miracle pill to boost fertility. Other possibilities include creating sperm free from inherited genetic conditions and using cloning techniques to create sperm which is a perfect genetic match for an infertile man.
In time, similar techniques may be developed to treat infertile women.
The Newcastle researchers now want to try out the technique on cells gleaned from human embryos. However, ethical and safety concerns mean it is unlikely they will be allowed to use any sperm they manage to make to fertilise eggs and create embryos.
'Breakthrough'
British scientists described the latest research, which is published in the journal Developmental Biology, as a 'hugely significant breakthrough'.
The warned, however, that much more work is needed before the technique could be applied to humans.
Dr Allan (CORR) Pacey, a Sheffield University specialist in male fertility, said: "To be able to make functional sperm in the laboratory will be very useful to study the basic biology of sperm production.
"There are currently many things we don't know about how sperm are formed, let alone why it sometimes goes wrong and leads to infertility in some men. "It is more difficult to say whether artificial sperm produced in this way would ultimately be used as a new treatment for male infertility. There are many technical, ethical and safety issues to be confronted before this could even be considered."
Sheffield University colleague Professor Harry Moore said: "These processes in the test-tube are far from perfect as the mice were abnormal.
"We therefore have to be very cautious about using such techniques to treat men or women who are infertile until all safety aspects are resolved. This may take many years."
Critics say it is wrong to experiment on human embryos and question whether any flaws in the sperm will be passed down to future generations. Josephine Quintavalle (CORR), of Comment on Reproductive Ethics, said: "At this stage, things are going very wrong. The further you deviate from the norm, the more likely you are to create more problems than you bargained for."
Mike Judge, of the Christian Institute, said: "Any move that could potentially take fathers out of parenting is always something that could be worrying."
By FIONA MACRAE, Daily Mail
Be Open-Minded When Seeking for Help
Who said infertility is conventionally a woman thing? Isnt it that male infertility produces great impact to conception? Now who is at the risk of infertility? Who is to be blamed?
Infertility is not a sole problem that is faced by women.
As most cultures practice, infertility is typically blamed on the part of the women. They are obviously wrong. There is nobody to be blamed for the matter. The inability to bear a child can be caused by several factors that are affecting both the couple. There is also the renowned male factor which means that the problem lies on the part of the male.
The concept of male infertility is no longer a new term these days. Medical findings have long started to point on the male reproductive system as a primary cause of infertility. But then because of mens too much pride, they find it hard to bring about acceptance for men infertility. There are no recognized symptoms or signs of men infertility. They can only be detected by the routinely health checkups. As couples, you need to be aware of your fertility status. Women are not always the ones at fault when it comes to the incapacity to bear a child. Men infertility should be accepted with an open mind.
In the available studies and reports that medical teams have further gathered, they see that men infertility comprises at lest 1/3 of its overall total. In contrast with the female reproductive system, the male reproductive system is less complicated. Men infertility is usually associated with the problem in sperm count and other known sperm disorders. The fertility process commonly takes place during the intercourse when there are millions of sperm cells that get deposited into the vagina during the male ejaculation. Only a few of the semen can successfully get through the protective walls of the egg cell to enable pregnancy. Therefore, the more sperm cells that are able to go through the eggs protective walling, the more chances of allowing a successful fertilization. For a progressive fertilization, the sperm quality, sperm size and shape, sperm motility, and sperm count are great factors to consider.
Logically, any problem with any of these factors is likely to bring about a difficulty in male fertility. The explanation to this is that a great number of sperm count and an optimum quality of sperm cells are sure to give a hundred percent male fertility.
Men infertility is likewise confronted with an array of environmental and health issues which can affect the difficulty in conceiving. The age is a renowned factor. Obviously, as man ages, his capacity to reproduce lessens. Specialists say that from the age of 35, the sperm cell quality starts to diminish. Ones lifestyle choices also pose an impact to men infertility. Men infertility is likely to be affected by the intense exposure to heat and by using overly tight underwear, the extreme exposure to pesticides, electromagnetic emissions, radioactivity and other hazardous substances. It is also to be noted that men infertility is greatly brought about by STDs, too much use of drugs, smoking, and the abuse of alcohol.
by David Fresco
Infertility can be traced to the male in 30 to 50 percent of all cases. That's not a statistic that many are aware of, but so says Dr. Mark Leondires, medical director for Reproductive Medicine Associates of Connecticut. Historically, other than being told to stay away from hot tubs and switch to boxer shorts, male infertility issues weren't given a lot of attention. Fortunately, this is changing as science begins to investigate the genetic link in male infertility.
Beyond Sperm Counts
When a couple seems to be experiencing infertility issues, there are some basic physiological conditions that should be evaluated before any more intensive testing is done. "One of the things I tell my patients is that there are three basic components to fertility," says Dr. Leondires. "These are regular ovulation, open fallopian tubes and a good sperm count. Since sperm is easily accessible, that should be done first."
Unfortunately, it doesn't always work that way. "Even in the medical community, there's what I call medical sexism," says Dr. Leondires. "I just saw a patient the other day who discovered the problem was with her husband only after she'd been through four cycles of Clomid."
In the male, in addition to a simple semen examination, diagnosing male factor infertility should include a thorough exam to rule out obvious physical defects of the reproductive system, as well as hormonal deficiencies. Once these factors are eliminated, the semen analysis can help the physician diagnose a host of possible problems that may be a factor in infertility.
"In examining a semen analysis, sperm count becomes just one component," says Dr. Mark Perloe, medical director of Georgia Reproductive Specialists. "A semen analysis is like a UPS tracking number; it can tell us if the sperm is likely to get to the egg. Unfortunately, if the outside of the box is damaged, there may be some damage inside. Sometimes, physicians will overlook the underlying information, such as the presence of immature cells and clues that there may be some infection or abnormality that's damaging the sperm."
The Genetic Component
While any test for male factor infertility begins with a sperm count, a high sperm count isn't necessarily an indicator of fertility. For example, many men have adequate sperm and semen production, yet still receive a diagnosis of infertility because their sperm is not effective at penetrating the egg to achieve fertilization. Sometimes, seemingly healthy sperm may have a genetic abnormality.
"Whenever you see a case of severe male factor infertility, part of workup should be a chromosomal analysis," says Dr. Leondires. "There have been a lot of recent findings on microdeletions of the Y chromosomes that are crucial genes for sperm production."
Aside from these microdeletions, which occur at a cellular level and are tricky to diagnose, other genetic factors include existing genetic conditions such as cystic fibrosis and polycystic kidney disease. Another important genetic component is age, which is an especially important consideration as people tend to have families at later and later ages.
"There is new data coming out of IVF literature suggesting that men over the age of 60 have more breakdown in their sperm genetics and that there may be a higher incidence of various disorders with older men," says Dr. Leondires. "Men probably have a biological clock just as women do, but the magnitude of its affect is smaller. We're just learning about this because it's only been recently that there have been enough men over the age of 60 trying to reproduce for us to even gather these statistics."
Many of these factors can be overcome by advances in reproductive medicine, such as IVF (in vitro fertilization) and ICSI (intracytoplasmic sperm injection), but it's also important to consider the risk of passing on genetic abnormalities to the next generation without more careful sperm and semen analyses.
No More Jokes
Overall, genetic research into male infertility is in its infancy, but the subject has taken on a new urgency as something that was once a joke in the reproductive field appears to be reality: the possible extinction of the male of our species. "We don't think it's our imagination anymore," says Dr. Leondires. "There definitely appears to be lower global sperm counts. We don't know why this is. It may be environmental, or it may be because since there's only one Y chromosome, the DNA and amino acids are starting to break down."
One reason for the speculation that our environment may be the cause is because, to the great surprise of researchers, some of the lowest sperm counts were identified in America's heartland. The perception of this part of the country may be of a healthy, corn-and-beef-fed population, but, in fact, the chemicals used in agriculture over the years have made it particularly toxic.
Regardless of the reason, the breakthroughs in genetic causes for male infertility can help promote treatment at the genetic level, even though those treatments may be many years down the road. "I think we're very far away from being able to manipulate the human genome to offer much hope at this point for treating infertility at the genetic level," says Dr. Leondires. "Human reproduction seems simple enough, but in reality it's extremely complicated, and there is still a lot we don't understand about how it all works."
By Kelly Burgess
Infertility may be becoming more of a man's than a woman's problem, new figures suggest. Until now, both were level pegging - 40% of cases linked to men, 40% to women and 20% to joint problems. However, the European Society for Human Reproduction and Embryology found rates of an IVF treatment typically used to help male infertility have risen. It said a number of factors including declining sperm quality due to environmental toxins may be involved. A male problem Use of ICSI (intra-cytoplasmic sperm injection), in which a single sperm is injected into the egg to fertilise it, made up only 43% of IVF cycles in 1997, but accounted for 52% of cycles in 2002. There were more than 122,000 ICSI cycles and nearly 113,000 IVF cycles in 2002, the ESHRE committee announced at its annual meeting in Copenhagen on Wednesday. The data came from 24 European countries. Dr Anders Nyboe Anderson, coordinator of the committee, said: "We do not really know why ICSI has become more prevalent. There are probably many reasons." It could be that the causes of infertility are shifting. He added: "We see less and less infertility caused by severe tubal [fertility tube] problems in women, probably because of better sexual protection due to the risk of Aids during the last 15 years." However he said the data on male subfertility showed it appeared to be increasing. Age-related problems Dr Anderson said: "Maybe environmental factors are playing an increasing role as the planet becomes more polluted and factors that disrupt the endocrine system are in the food chain." But he said it was more likely that ICSI was becoming the preferred method of assisted reproduction, as the technique has improved since its introduction in the early 1990s. He said private clinics tended to use ICSI rather than IVF to improve the chance of success first time, even though both techniques have the same take-home-baby rate. Another theory is that men, like women, are increasingly putting off starting a family until they are older, when fertility is lower, Dr Anderson said. More and more men aged 50-65 are now attending fertility clinics - men over 40 making up nearly a quarter of consultations, the study said. Impact In separate research, a team of Canadian scientists have found damage to DNA in sperm increases with age. By analysing the sperm of 2,134 men they found a wide variation in quality that was linked with age. DNA damage was far higher in men over 45 than in younger men - men aged 45 had double the damage of those younger than 30. He said data from the US showed that the birth rate for fathers older than 35 had increased by nearly 20% between 1980 and 1995. Lead author Dr Sergey Moskotsev, of the Mount Sinai Hospital in Toronto, told the ESHRE conference: "The effect of age on male infertility is particularly interesting because of the growth in the number of men choosing to father children at older ages. "The combination of increased female factor infertility, increased sperm DNA damage, low levels of DNA repair and increased abnormalities in conventional semen parameters will have a pronounced impact on their reproductive potential." Dr Allan Pacey, Senior Lecturer in Andrology at the University of Sheffield and Secretary of the British Fertility Society, said: "This should remind us that the male reproductive system is not immune from the effects of ageing. "Whilst the effects of aging are not as dramatic as are seen in women, subtle changes in DNA quality could seriously affect a couple's ability to conceive, or could lead to miscarriage or even health problems in any children born. "Having a family when you are younger is always a good plan."
By Michelle Roberts
BBC News health reporter in Copenhagen
A potential cure for male infertility has been discovered by scientists. In a major breakthrough, researchers have for the first time succeeded in using artificially-grown sperm to fertilise eggs.(Left Photo:Seven baby mice were born under the ground-breaking process)
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