Sperm May Feel the Weight of Extra Pounds: Study

By Genevra Pittman

Worldwide - Heavy men are more likely than their normal-weight peers to have low sperm counts or no sperm production at all, suggests a new report.

The review of past studies can't prove that overweight or obese men will have more trouble fathering a child. But researchers said that how many sperm men make is one of the key ways doctors measure their fertility.

"In general you expect that men with lower sperm counts will have a greater frequency of difficulty conceiving than men with higher sperm counts, but it's not completely straightforward," said Dr. Jorge Chavarro, from the Harvard School of Public Health, part of the collaborative group that put out the study.

How well sperm move, their shape and the quality of DNA they carry matter too, Chavarro said -- but previous studies have suggested some of those measures of sperm quality may be affected by obesity as well. For the new analysis, French researchers combined data from 14 studies that compared sperm count in samples of ejaculate from normal weight, overweight and obese men, as well as data from their own infertility center.

About one-quarter of the combined 10,000 men had a low sperm count. In another analysis, just over 250 out of almost 7,000 men had no sperm in their ejaculate at all.

Dr. Sebastien Czernichow, from the Ambroise Pare Hospital, Boulogne-Billancourt, and colleagues calculated that compared to normal-weight men, overweight men were 11 percent more likely to have a low sperm count and 39 percent more likely to have no sperm -- though it's possible the second finding was due to chance.

Obese men, on the other hand, were 42 percent more likely to have a low sperm count than their normal-weight peers and 81 percent more likely to have sperm-free ejaculate, the researchers reported in the Archives of Internal Medicine.

They proposed a number of different theories for the findings, including that male hormones may be converted into estrogen in fat tissue, affecting sperm-making down the line, or that more fat in the hips and stomach could make the scrotum too hot.

The results don't prove that overweight and obese men will have more fertility trouble -- although you wouldn't expect men who have no sperm at all to be fertile, Chavarro said. And it's possible that the obesity itself isn't to blame; rather, in some men, an underlying health condition causes them to gain weight and affects their sperm, said Dr. Stephen Winters, Professor of Medicine and Chief of the Division of Endocrinology, Metabolism and Diabetes at the University of Louisville.

Because of that, researchers can't say for sure whether heavy men could boost their sperm production by losing weight. Czernichow told Reuters Health in an email that losing weight improves fertility in women, but that there's not much data in men -- though small case reports have suggested weight-loss surgery may actually have a negative effect on sperm.

The findings jibe with a study from late last year which found that being overweight was tied to a lower sperm concentration and lower motility -- how well sperm swam.

The current report "is not conclusive, and the risks are not huge," Winters, who wasn't involved in the research, told Reuters Health. But fertility trouble, he added, "is there among the health risks of obesity."
"This appears to be yet another health outcome for which maintaining a healthy weight appears to be important," Chavarro told Reuters Health.

"It's not only about your cardiovascular disease risk, it's not only about diabetes and some forms of cancer. Obesity also seems to affect outcomes that may be manifested in younger men."

Study Shows Doctors Over-treat Urine Bacteria

By Genevra Pittman

Reuters Health - In a new study of patients with bacteria in their urine, doctors prescribed antibiotics to one in three who had no symptoms and no evidence of a urinary tract infection.

In those cases, the bacteria probably would have disappeared on their own without causing any problems, researchers said, and treating those patients with drugs goes against guidelines -- because it increases the risk of antibiotic resistance without any real benefit.

"When the average physician sees a positive (for bacteria) urine culture, they automatically think of treating," said Dr. Peter Gross, an infectious diseases specialist at Hackensack University Medical Center in New Jersey who was not involved in the new study.

Gross told Reuters Health that many doctors are afraid of the consequences -- such as getting sued -- if they decide not to treat bacteria in the urine and it does develop into something more serious. Others, he added, might equate a positive test for bacteria with a urinary tract infection, or UTI, without thinking about other options.

In the new study, researchers from the Houston, Texas, Michael E. DeBakey Veterans Affairs Medical Center and the MD Anderson Cancer Center analyzed the medical records of patients at their hospitals whose urine had tested positive for a specific type of bacteria in late 2009.

That included 339 specific cases. Most patients were older and male, and being treated in the hospital or emergency room when their urine was tested.

Based on information from the lab tests and notes on patient symptoms characteristic of a UTI -- such as fever and pain while urinating -- the researchers determined that 156 patients had an infection, while 183 had cases of so-called colonization, with no sign of infection.

In patients with UTI symptoms, doctors were almost 12 times more likely to prescribe antibiotics as in symptom-free cases, Dr. Barbara Trautner, of the VA, and her colleagues reported in the Archives of Internal Medicine this week.

Still, 60 patients out of the 183 without evidence of a UTI were treated with antibiotics, against guidelines from the Infectious Diseases Society of America.

Only in specific cases, such as in pregnant women, do guidelines recommend treating bacterial colonization in symptom-free people using antibiotics.

Hospital patients who need a catheter are especially likely to develop bacteria in the urine. If it's not a full-on infection, Gross said, those patients will probably clear any bacteria within a week after getting the catheter taken out -- without the help of antibiotics.

Trautner's team found few side effects associated with the antibiotics used in patients with or without a UTI.
That doesn't change the fact, they note, that using antibiotics when they're not called for contributes to drug resistance -- when bacteria no longer respond to one or more types of antibiotics and infections get more difficult to treat.

What's more, the most commonly used antibiotics in all patients with bacteria in their urine were quinolones, which are known as "broad-spectrum" antibiotics. Those drugs work against the widest range of bacteria, which means that resistance is a bigger concern with their overuse.

Many hospitals already have efforts in place to limit the unnecessary use of antibiotics, but Gross said the decision of when to use drugs still often requires a fair amount of judgment on the part of doctors. So patients' knowledge of appropriate and inappropriate use matters too, he said.

"There's nothing like an educated patient," Gross said. "Patients need to know that not every positive urine culture indicates infection, it could just indicate colonization."

When it comes to using antibiotics, he said, "I agree with, 'less is more.'"