Declining sperm theory out for the count

Claims that men are suffering from a mysterious decline in their sperm counts that could eventually imperil the future of the human race are being dramatically challenged by scientists in the United States.

Three new studies into male fertility suggest that sperm counts among American men, at least, have actually increased slightly in the last twenty years. There is also intriguing evidence that residents of New York City consistently demonstrate far higher sperm counts than men in other US cities.

While the revelation hands welcome machismo rights to all Big Apple males, it is also the basis for another important conclusion; that previous studies suggesting falling sperm counts were grievously flawed because they failed to take such geographical variations into account.

A Danish scientist first alerted the world to the possibility of declining sperm counts in 1992, showing that sperm counts among 15,000 men in 20 countries had dropped by almost half in 50 years. Two subsequent studies, in Belgium and France, drew similar conclusions, and raised concern over the quality of sperm.

The new findings, which are certain to provoke furious debate in the medical fraternity, are detailed in three reports in this month's issue of the US journal, Fertility and Sterility.

One study analysed the semen of 1,283 men who made deposits to sperm banks in three cities - Los Angeles, New York and Roseville, Minnesota - from 1970 to 1994. Its author, Dr Harry Fisch of the Columbia-Presbyterian Medical Center in New York, found a "slight but significant increase".

There may be no explaining - scientifically anyway - the elevated sperm counts of New York men, who boast 131.4 million sperm per millilitre of semen. That is more than 50 per cent higher than the measly 72.7 million registered by men living in Los Angeles.

Much more important, says Dr Fisch, is to understand the main bodies of research that have suggested worldwide declines in sperm counts were misleading because they compared new data gathered in Europe and the Third World with earlier results from New York, where the counts have always been high. "Take New York out of those studies, and there is no decline," he said yesterday.

Non-scientific speculation about sperm-heavy New Yorkers is already under way. Among the theories: LA guys spend too much time in hot tubs (not good for the testicles), tight shorts (likewise) and in fitness gyms. Or there is the supply-and-demand angle: New Yorkers have more sex than men anywhere else.

PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
News
ebooksAn unforgettable anthology of contemporary reportage
Life and Style
Britons buy more than 30 million handsets each year, keeping them for an average of 18 months
tech
Arts and Entertainment
Alloysious Massaquoi, 'G' Hastings and Kayus Bankole of Young Fathers are the surprise winners of this year's Mercury Music Prize
musicThe surprise winners of the Mercury Prize – and a very brief acceptance speech
Arts and Entertainment
TV Presenters Ant McPartlin and Dec Donnelly. Winners of the 'Entertainment Programme' award for 'Ant and Dec's Saturday Night Takeaway'
musicAnt and Dec confirmed as hosts of next year's Brit Awards
Arts and Entertainment
Orson Welles made Citizen Kane at 25, and battled with Hollywood film studios thereafter
film
News
video
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

English Teacher

£100 - £125 per day: Randstad Education Chelmsford: English Teacher - Saffron ...

Primary Supply Teacher - Northants

£90 - £130 per day: Randstad Education Leicester: Primary School Supply Teache...

Maths Teacher

£21000 - £35000 per day: Randstad Education Chelmsford: Maths Teacher - Saffro...

Chemistry Teacher - Top School in Malaysia - January Start

£18000 - £20400 per annum + Accommodation, Flights, Medical Cover: Randstad Ed...

Day In a Page

Isis in Syria: A general reveals the lack of communication with the US - and his country's awkward relationship with their allies-by-default

A Syrian general speaks

A senior officer of Bashar al-Assad’s regime talks to Robert Fisk about his army’s brutal struggle with Isis, in a dirty war whose challenges include widespread atrocities
‘A bit of a shock...’ Cambridge economist with Glasgow roots becomes Zambia’s acting President

‘A bit of a shock...’ Economist with Glasgow roots becomes Zambia’s acting President

Guy Scott's predecessor, Michael Sata, died in a London hospital this week after a lengthy illness
Fall of the Berlin Wall: History catches up with Erich Honecker - the East German leader who praised the Iron Curtain and claimed it prevented a Third World War

Fall of the Berlin Wall

History catches up with Erich Honecker - the East German leader who praised the Iron Curtain and claimed it prevented a Third World War
How to turn your mobile phone into easy money

Turn your mobile phone into easy money

There are 90 million unused mobiles in the UK, which would be worth £7bn if we cashed them in, says David Crookes
Independent writers remember their Saturday jobs:

Independent writers remember their Saturday jobs

"I have never regarded anything I have done in "the media" as a proper job"
Lyricist Richard Thomas shares his 11-step recipe for creating a hit West End musical

11-step recipe for creating a West End hit

Richard Thomas, the lyricist behind the Jerry Springer and Anna Nicole Smith operas, explains how Bob Dylan, 'Breaking Bad' and even Noam Chomsky inspired his songbook for the new musical 'Made in Dagenham'
Tonke Dragt's The Letter for the King has finally been translated into English ... 50 years on

Buried treasure: The Letter for the King

The coming-of-age tale about a boy and his mission to save a mythical kingdom has sold a million copies since it was written by an eccentric Dutchwoman in 1962. Yet until last year, no one had read it in English
Can instilling a sense of entrepreneurship in pupils have a positive effect on their learning?

The school that means business

Richard Garner heads to Lancashire, where developing the 'dragons' of the future is also helping one community academy to achieve its educational goals
10 best tablets

The world in your pocket: 10 best tablets

They’re thin, they’re light, you can use them for work on the move or keeping entertained
Lutz Pfannenstiel: The goalkeeper who gave up Bayern Munich for the Crazy Gang, Bradford and a whirlwind trawl across continents

Lutz Pfannenstiel interview

The goalkeeper who gave up Bayern Munich for the Crazy Gang, Bradford and a whirlwind trawl across continents
Pete Jenson: Popular Jürgen Klopp can reignite Borussia Dortmund’s season with visit to Bayern Munich

Pete Jenson's a Different League

Popular Klopp can reignite Dortmund’s season with visit to Bayern
John Cantlie video proves that Isis expects victory in Kobani

Cantlie video proves that Isis expects victory in Kobani

The use of the British hostage demonstrates once again the militants' skill and originality in conducting a propaganda war, says Patrick Cockburn
The killer instinct: The man who helps students spot potential murderers

The killer instinct

Phil Chalmers travels the US warning students how to spot possible future murderers, but can his contentious methods really stop the bloodshed?
Clothing the gap: A new exhibition celebrates women who stood apart from the fashion herd

Clothing the gap

A new exhibition celebrates women who stood apart from the fashion herd
Fall of the Berlin Wall: Goodbye to all that - the lost world beyond the Iron Curtain

The Fall of the Berlin Wall

Goodbye to all that - the lost world beyond the Iron Curtain