Men and teenage boys who use laptop computers may be damaging their fertility. The combination of the heat generated by the computer and the posture needed to balance the machine...

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Men’s health

Computer on lap may zap fertility

Men and teenage boys who use laptop computers may be damaging their fertility. The combination of the heat generated by the computer and the posture needed to balance the machine on the lap increases the temperature around a man’s scrotum, which in the long term may reduce his fertility, according to researchers at the State University of New York at Stony Brook.

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The study found that sitting with thighs together while balancing a laptop causes temperatures in the scrotum to rise by as much as 5 degrees Fahrenheit. The research was published in the December issue of Reproduction Journal.

“Until further studies provide more information on this type of thermal exposure, teenage boys and young men may consider limiting their use of laptop computers on their laps, as long-term use may have a detrimental effect on their reproductive health,” lead researcher Yefim Sheynkin, an associate professor of urology and director of male infertility and microsurgery at the university, said in a statement on the journal’s Web site.

The study, which the journal said is the first research into a possible laptop-fertility link, measured scrotal temperatures in men with and without laptops. Two brands of computers were used by 29 healthy volunteers from 21 to 25.

Size is “vital sign”

Larger waist poses heart-disease risk

The best tool for predicting the risk of heart disease may be a tape measure, researchers say.

Studies presented at a meeting of the American Heart Association show that having a big waist may be a fast route to a heart attack or serious heart disease.

“Waist circumference is a vital sign,” said Dr. Robert Eckel, a heart expert at the University of Colorado and president-elect of the American Heart Association.

Doctors check cholesterol levels, blood pressure and obesity to measure the risk of heart disease, by far the No. 1 cause of death in the United States and much of the world.

Smoking remains the greatest cause of death from heart disease, but obesity is catching up. Statistics have also started to show clearly that where fat goes on the body is important — an “apple” shape with fat in the middle is more dangerous than a bottom-heavy “pear” shape.

In the case of men, a 40-inch waist seems to be the dangerous cut-off point. For women, the risk starts at 30 inches.

Australian study

No lingering effect on ultrasound babies

In one of the few studies looking specifically for side effects of ultrasound, researchers from the School of Women’s and Infants’ Health in Australia published data more than 10 years ago suggesting that ultrasounds may slow growth in the womb. In that research, the scientists compared the size of newborns who had gotten five ultrasounds to newborns who had received only one ultrasound at 18 weeks gestation.

Those researchers followed the infants for eight more years. Writing in the journal The Lancet, the scientists reported that any differences in size disappeared as the children aged. Although the findings are reassuring, the scientists said, studies on ultrasound should continue as technology evolves because the practice is a standard but relatively understudied part of prenatal care.

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