Farm pesticides lower sperm count

[Guest guest]

Sperm Quality Poorer in Rural Men

1 hour, 20 minutes ago

By Kathleen Doheny

HealthScoutNews Reporter

 

MONDAY, Nov. 11 (HealthScoutNews) -- Men who live in rural parts of the United

States have poorer sperm quality than men in urban areas, a new study contends,

and farm pesticides may be to blame.

 

 

 

Males in Columbia, Mo., had lower sperm quality than men in New York City, Los

Angeles or Minneapolis, says lead researcher Shanna Swan, an epidemiologist and

research professor of family and community medicine at the University of

Missouri, Columbia.

 

 

The study appears in the November issue of the journal Environmental Health

Perspectives.

 

 

Swan's team studied 512 men, all partners of pregnant women receiving prenatal

care at clinics in the four study sites, and analyzed 903 sperm samples. Even

though some of the men had lower sperm quality, it was not substandard enough to

prevent them from getting their partners pregnant, she points out.

 

 

Still, the finding is of concern and her team will investigate further.

 

 

The total number of motile (moving) sperm was lowest in the rural men. The

Missouri men averaged 113 million motile sperm per sample, considered a very low

count, compared to 201 million in the Minneapolis men, which is considered very

healthy, Swan says. The New York City men averaged 196 million motile sperm, and

the Los Angeles men, 162 million.

 

 

Put another way, the total motile count (which takes into account concentration

of sperm, volume of sperm and the percent that are mobile) was 58 percent lower

in the Missouri men than in Minneapolis men.

 

 

When she and her researchers looked at another measure of fertility, the

concentration of sperm per milliliter, Swan says they also found the rural men

fared worst.

 

 

" A concentration of under 40 million sperm per milliliter is considered reason

for concern by some experts, and a substantial number of the Missouri men had

concentrations below 40, " she says.

 

 

The findings came as a " total surprise " to Swan, who had assumed before the

study that the urban dwellers might have lower sperm quality due to air

pollution.

 

 

Exposure to agricultural chemicals is thought to be the cause, but Swan

emphasizes that more research is needed before that can be proven. Her team

controlled for age, smoking, history of infertility and other factors that might

affect sperm quality.

 

The Columbia area is heavily agricultural, with 57 percent of the land used for

farming. In the three urban areas studied, only 19 percent or less of the land

is used for farming, and in some cases none of the land is devoted to farming.

 

Blaming agricultural chemicals is a " natural guess, " Swan says. " There are

animal studies that show pesticides affect fertility, " she says.>/p>

 

The study comes as no surprise to fertility experts.

 

" There has been a lot of evidence that pesticides are harmful to men, " says Dr.

Cappy Rothman, a male infertility expert and medical director of the California

Cryobank in Los Angeles, a sperm bank.

 

He recalls a man coming to him in the late 1980s for infertility treatment who

had grown up in a rural area of Bakersfield, Calif., and drank well water that

was later found to be contaminated with farming chemicals.

 

While it couldn't be proven that the chemicals in the drinking water led to the

man's fertility problems, Rothman says they could have been the cause.

 

He praises the Swan study but says it begs more questions. " Sperm are dying, " he

says. " So what about the rest of the body? Are kids affected in utero, or later?

And what about women? "

 

Susan Benoff is president of the Society for Male Reproduction and Urology, and

she says " the idea that there are differences in geographic areas [in semen

quality] makes sense. "

 

The question that needs to be answered next, she adds, is why.

 

Swan agrees. Her team is planning additional research in Iowa City, Iowa, an

area where exposure to farming chemicals is even higher than in Columbia. She

hopes to collect sperm samples from men in that area and to replicate the

four-center study, to determine why rural men seem to suffer from poorer sperm

quality.

 

She adds, however, that her study shouldn't spark alarm among rural couples

trying to get pregnant. Women can get pregnant from a reduced sperm count, but

it may take longer, she says.

 

What To Do

 

For more information on infertility, see the American Society for Reproductive

Medicine.