Saturday, April 28, 2007

The sperm count scare again: More absurd reasoning

The original headline on this article is "Fertility treatment 'reduces sperm in offspring'". But the very last sentence below fingers the real problem: Women with low fertility have children with low fertility

SPERM counts in the first generation of men born after their mothers received fertility treatment appear to be nearly 50 per cent lower than in men conceived naturally. The world's first study looking at the fertility of children born after their mothers received fertility treatment two decades ago has found their sperm concentration was 46 per cent lower, and sperm counts 45 per cent lower than in other men.

Nearly 2000 Danish men volunteered to be examined as part of the research. In addition to having lower sperm counts, the 47 men whose mothers said they had conceived following fertility treatment were also found to have smaller testes, fewer sperm that "swam" as they are supposed to, and more sperm cell deformities compared with the other men.

The effect was more exaggerated in the 25 mothers who identified their form of fertility treatment as hormonal therapy - most likely to have been anti-oestrogen drugs to stimulate follicle growth and ovulation. Experts say almost all women receiving fertility treatment in Australia receive similar drugs.

The research, published earlier this year in the American Journal of Epidemiology, has become possible as the first generation of children born thanks to assisted reproduction techniques enter young adulthood and become sexually mature.

Fertility experts in Australia yesterday said the findings ought to be taken into account by couples considering assisted reproduction, including in-vitro fertilisation - rates of which are soaring in Australia. However, some expressed caution at the findings, saying Denmark has the world's highest rate of testicular cancer and results in Danish men could not be assumed to apply elsewhere without further research.

Fertility expert John Aitken, director of the ARC Centre of Excellence in Biotechnology and Development at the University of Newcastle, said the findings were "interesting and should be looked at more carefully" in Australia. "We have not seen anything like this before," Professor Aitken said. "It's data that should encourage us to look very carefully for the consequences of specific forms of treatment."

Sperm concentration was a median of 48 million per millilitre in the natural-born men, compared with 33 million in the men whose mothers had had fertility treatment, before statistical adjustments. The World Health Organisation defines the lower threshold of normal as 20 million sperm per millilitre. Thirty per cent of the fertility-treatment men were below this threshold, compared with 20 per cent of the normal-birth men. "The worry has always been that by bypassing biology, gametes (sperm and egg cells) are participating in conception in vitro that (they) would never have participated (in) in real life," Professor Aitken said.

Peter Illingworth, medical director of the private Sydney-based fertility clinic IVF Australia, said the study "may suggest ... a higher likelihood of reproductive health problems among boys conceived from fertility treatments". However, he said the men's sperm counts were still normal, and the study was consistent with previous research that found fertility-treatment children were at a slightly higher risk for a range of health problems.

It remained unclear whether this was because of the fertility treatment itself, or whether it reflected a continuation of their parents' fertility problems.


Doubtful diabetes drugs

Drugs to prevent type 2 diabetes probably do more harm than good, according to three specialists. They say that most patients at risk of developing the disease would be better advised to change their diets and do more exercise - interventions of proven benefit. The warning, from specialists at the Mayo Clinic in Rochester, Minnesota, and McMaster University in Hamilton, Ontario, appear to contradict directly the results of a widely publicised study of a new drug combination, ramipril and rosiglitazone.

A trial to test this combination in people who did not have diabetes but had evidence of poor glucose control was terminated early when results showed many fewer people progressing to diabetes proper. The Dream trial was hailed as evidence that diabetes could be prevented and the treatment, the three doctors say in British Medical Journal, is now being "aggressively marketed". The trial showed a 62 per cent reduction of the risk of progressing from impaired glucose tolerance to type 2 diabetes. But it also showed an increased risk of heart failure and no evidence of a fall in deaths.

Since diet and exercise changes have been shown to cut the risk of diabetes by 58 per cent, cost much less and do not have the effect of "medicalising" healthy people, they are to be preferred, says the team, led by Victor Montori, of the Mayo Clinic. They add that it was entirely possible that the improvements found in the Dream trial were the result of rosiglitazone treating diabetes rather than preventing it. That could be proved only by discontinuing treatment and observing whether people who had been treated progressed to diabetes more slowly than they otherwise would have done. Such a trial had not yet been done.

From the patients' point of view, it came down to the issue of whether they would prefer to take pills now in the hope of taking fewer pills later. That would be justified only if it could be shown that doing so would avoid the later complications of diabetes, which were severe. The trials had not shown this yet. "The benefits of rosiglitazone on outcomes important to patients remain speculative," the authors say.

The downside of taking "preventive" medicine was cost and healthy people being labelled as ill and becoming anxious as a result. "The threshold for use of drugs in otherwise healthy people must be set high," the doctors say. "Clinical use of glitazones to prevent diabetes is, at present, impossible to justify because of unproved benefit on patient-important outcomes or lasting effect on serum glucose, increased burden of disease labelling, serious adverse effects, increased economic burden and availability of effective, less costly lifestyle measures."

The Dream trial, published in The Lancetin September, suggested that as many as one in 12 people should be taking rosiglitazone to prevent diabetes. Simon O'Neill, of Diabetes UK, said: "The Medicines and Healthcare products Regulatory Agency state that rosiglitazone is a safe and effective treatment for those diagnosed with type 2 diabetes. Used as a preventative medication, the Dream study has shown that it can reduce the risk of developing the condition." He added, however, that Diabetes UK "strongly recommends that people at risk of developing type 2 diabetes should be incorporating increased levels of physical activity into their daily lives alongside making changes to their diet".



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.


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