Study Links Water Pollution With Declining Male Fertility

New research strengthens the link between water pollution and rising male fertility problems. The study, by Brunel University, the Universities of Exeter and Reading and the Centre for Ecology & Hydrology, shows for the first time how a group of testosterone-blocking chemicals is finding its way into UK rivers, affecting wildlife and potentially humans. The research was supported by the Natural Environment Research Council and is now published in the journal Environmental Health Perspectives

The study identified a new group of chemicals that act as 'anti-androgens'. This means that they inhibit the function of the male hormone, testosterone, reducing male fertility. Some of these are contained in medicines, including cancer treatments, pharmaceutical treatments, and pesticides used in agriculture. The research suggests that when they get into the water system, these chemicals may play a pivotal role in causing feminising effects in male fish.

Earlier research by Brunel University and the University of Exeter has shown how female sex hormones (estrogens), and chemicals that mimic estrogens, are leading to 'feminisation' of male fish. Found in some industrial chemicals and the contraceptive pill, they enter rivers via sewage treatment works. This causes reproductive problems by reducing fish breeding capability and in some cases can lead to male fish changing sex.

Other studies have also suggested that there may be a link between this phenomenon and the increase in human male fertility problems caused by testicular dysgenesis syndrome. Until now, this link lacked credence because the list of suspects causing effects in fish was limited to estrogenic chemicals whilst testicular dysgenesis is known to be caused by exposure to a range of anti-androgens.

Lead author on the research paper, Dr Susan Jobling at Brunel University's Institute for the Environment, said: "We have been working intensively in this field for over ten years. The new research findings illustrate the complexities in unravelling chemical causation of adverse health effects in wildlife populations and re-open the possibility of a human - wildlife connection in which effects seen in wild fish and in humans are caused by similar combinations of chemicals. We have identified a new group of chemicals in our study on fish, but do not know where they are coming from. A principal aim of our work is now to identify the source of these pollutants and work with regulators and relevant industry to test the effects of a mixture of these chemicals and the already known environmental estrogens and help protect environmental health."

Senior author, Professor Charles Tyler of the University of Exeter, said: "Our research shows that a much wider range of chemicals than we previously thought is leading to hormone disruption in fish. This means that the pollutants causing these problems are likely to be coming from a wide variety of sources. Our findings also strengthen the argument for the cocktail of chemicals in our water leading to hormone disruption in fish, and contributing to the rise in male reproductive problems. There are likely to be many reasons behind the rise in male fertility problems in humans, but these findings could reveal one, previously unknown, factor."

Bob Burn, Principal Statistician in the Statistical Services Centre at the University of Reading, said: "State-of-the-art statistical hierarchical modelling has allowed us to explore the complex associations between the exposure and potential effects seen in over 1000 fish sampled from 30 rivers in various parts of England."

The research took more than three years to complete and was conducted by the University of Exeter, Brunel University, University of Reading and the Centre for Ecology & Hydrology. Statistical modelling was supported by Beyond the Basics Ltd.

The research team is now focusing on identifying the source of anti-androgenic chemicals, as well as continuing to study their impact on reproductive health in wildlife and humans.

New Treatment For Common Cause Of Male Infertility

Researchers in Germany found that a simple and minimally invasive outpatient treatment for varicoceles, a common cause of male infertility that affects about 1 in 10 men, can significantly improve sperm function and pregnancy rates.

The study came from the University of Bonn Medical School and is published in the August issue of Radiology.

Lead author Dr Sebastian Flacke and colleagues found that the level of sperm motility present before having the treatment was also an important predictor of pregnancy success.

Flacke is now an associate professor of radiology at the Tufts University School of Medicine, director of noninvasive cardiovascular imaging and vice chair for research and development in the department of radiology at the Lahey Clinic in Burlington, Massachusetts.

He said that:

"Venous embolization, a simple treatment using a catheter through the groin, can help to improve sperm function in infertile men."

"With the patients' improved sperm function, more than one-quarter of their healthy partners were able to become pregnant," added Flacke.

Varicoceles is a condition like varicose veins where the blood vessels in the scrotum become tangled and swollen. Normally the blood flows from the testicles back to the heart via small veins that have a non-return valve to stop the blood flowing backwards to the testicles. But if these valves stop working, then the blood backs up, fails to leave the testicles properly and causes the vessels to bulge and swell.

Varicoceles is a common condition that generally has no symptoms or harmful side effects and affects between 10 and 15 per cent of adult men in the US. Figures from the National Institutes of Health suggest it mostly affects young men between 15 and 25. Occasionally the condition results in pain, shrinkage, or fertility problems.

Until recently, men with problematic varicoceles were treated with open surgery to remove the affected blood vessels, but now there is a minimally invasive procedure called catheter embolization which a man can have as an outpatient. Catheter embolization is where the radiologist inserts a small tube or catheter through a tiny cut in the groin, and using x-ray imaging, guides the catheter to the affected blood vessel and then blocks it using a platinum coil and a few millillitres of a liquid agent. The patient recovers quickly and is usually well enough to go back to work in 24 hours.

For this study, in order to identify what might affect pregnancy rates in couples where the man was infertile before undergoing varicocele embolization, Flacke and colleagues recruited 223 infertile men aged between 18 and 50 who had been diagnosed with at least one varicocele and who underwent embolization. All the men had healthy partners with whom they had been trying to conceive.

Before and after the procedure, all participants underwent a clinical exam (with ultrasound test), gave a semen specimen, and had their hormone levels tested.

The results showed that:226 of the patients' 228 varicoceles were successfully treated with embolization.

Follow up data was successfully obtained for 173 patients, and in these, three months after the procedure, the average sperm motility and sperm count was found to be significantly improved.

Six months later, 45 couples (26 per cent of the 173 followed up), reported a pregnancy.

The only significant pre-treatment predictor of post-treatment pregnancy success was sperm motility.

Other measures such as hormone levels, clinical grading of varicoceles, Doppler ultrasound findings, and other semen parameters did not reach statistical significance.
Flacke said:

"Embolization of varicoceles in infertile men may be considered a useful adjunct to in-vitro fertilization."

"Embolization of Varicocles: Pretreatment Sperm Motility Predicts Later Pregnancy in Partners of Infertile Men."
Sebastian Flacke, Michael Schuster, Attila Kovacs, Marcus von Falkenhausen, Holger M. Strunk, Gerhard Haidl, and Hans H. Schild.
Radiology 2008 248: 540-549.
Volume 248, Issue 2, August 2008
DOI: 10.1148/radiol.2482071675.

Singapore Airlines

A mother and her young inquisitive son were flying Singapore
Airlines from Singapore to New York.

The son (who had been looking out the window) turned to his mother
and asked, "If dogs have baby dogs and cats have baby cats, why
don't planes have baby planes?"

The mother (who couldn't think of an answer) told her son to ask the
pretty flight attendant.
So the boy dutifully asked the flight attendant, "If dogs have baby
dogs and cats have baby cats, why don't planes have baby planes?"

The flight attendant asked, "Did your mother tell you to ask me
that?" The little boy admitted that she did.

"Well, then, tell your mother that there are no baby planes because
Singapore Airlines always pulls out on time. Now, let your mother
explain that to you!!!"

How Do The Iraqis Hide From The Yanks

Expired Banks

Peanuts Forever

Malignant Conditions In Children Born After Assisted Reproductive Technology

A recent article article reviews the risks of childhood malignancies and imprinting disorders in children born as a result of assisted reproductive technology (ART) (Bibliography at the end of this post). Since the birth of Louise Brown, there have been 3 million babies born by IVF. Factors which have been implicated in potentially increasing the risk of malignancies in these offspring include:

1. gonadotropins for superovulation,
2. intracytoplasmic sperm injection,
3. blastocyst culture,
4. assisted hatching,
5. and preimplantation genetic diagnosis.

For example, whereas, a significant risk of neuroblastoma, retinoblastomas, acute lymphatic leukemia and non-Hodgkin lymphoma has been reported after ART, others have failed to replicate these findings.

Epigentic alterations leading to DNA modifications and imprinting disorders have also been implicated as a result of assisted reproductive techniques. Two genetic imprinting disorders that are known to cause birth defects and childhood malignancies, Beckwith-Wiedmann syndrome and Angelman syndrome. Each of these have been associated with ART.

The current paper provides a literature review that was unable to identify the precise risks of imprinting disorders and childhood cancers in children conceived with ART.

Although, most studies have not shown an increase in the incidence of childhood cancers after ART, patients should be advised about the known and unknown associated risks.

Neelanjana M, Sabaratnam A
Obstet Gynecol Surv. 2008 Oct;63(10):669-76