Led by Jorma Toppari, MD, PhD, of the University of Turku, researchers examined three cohorts of 19 year old men between the years of 1998 and 2006. The men that were born in the late 1980s had lower sperm counts than those who were born in the beginning of the 1980s. The total sperm counts were 227 million, 202 and 165 for men born in 1979-81, 1982-83 and 1987, respectively. Less than 10 % of sperm are structurally normal, and the number of morphologically normal sperm declined from 18 million to 11.
At the same time, the younger and more recently born men also had higher incidences of testis cancer than the older generations. The incidence rate is many fold higher for Finns born around 1980 compared with men born around 1950.
The underlying cause for these simultaneously occurring adverse trends remains unknown. However, the rapid change strongly points to environmental reasons. Endocrine disrupting compounds acting during development have been hypothesized to be a cause.
"Our findings further necessitate the efforts to identify reasons for the adverse trends in reproductive health to make preventive measures possible," Toppari notes.
Amy Molnar | EurekAlert!
Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung
Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
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For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
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An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
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