Rob Stein

Scientists were able to make immature sperm cells. If they can make the sperm viable, researchers could help men who thought they'd never have kids. But the findings also raise ethical questions.

By surgically transplanting material from pig bladders into the injured legs of several men, doctors prompted muscles to heal by growing and nurturing fresh, healthy cells.

A botched execution in Oklahoma is only the latest issue since states started having trouble obtaining the drugs used to execute inmates. They've been trying new combinations and new ...

The Food and Drug Administration is proposing to expand its regulatory powers to e-cigarettes and other popular products containing nicotine.

If the agency has its way, it will ban sales to minors and keep e-cigarettes out of vending machines. People also would be warned that the nicotine vapor the devices emit is addictive.

The developer of Moxduo says the drug, which combines morphine and oxycodone, would provide faster pain relief. But reviewers say there's not enough evidence that the combination drug is safer.

The FDA is weighing the pros and cons of a drug that would, for the first time, combine morphine and oxycodone in a single pill. Critics warn that it could launch a new wave of abuse.

To see if low blood sugar sours even good relationships, scientists used an unusual tool: voodoo dolls representing spouses. As hunger levels rose, so did the number of pins.

Garrett Peterson was born with a defective windpipe and every day he struggled to breathe. Now, thanks to a 3-D printer, his windpipe has been strengthened and Garrett should soon breathe normally.

Research involving more than 1,500 patients suggests people with Crohn's may have too many of the types of gut bacteria that tend to rile the immune system and too few that reduce inflammation.

Sequencing someone's genetic code may seem a good way to raise warnings on health risks. But results can be a confusing mess of information that only leaves patients and doctors needlessly scared.

A pregnant woman's blood contains enough fetal DNA for doctors to check whether the baby would be born with Down syndrome. A new blood test is safe and accurate, but it raises ethical concerns.

Researchers say they can replace DNA in human eggs with genetic material from another woman to prevent devastating disorders in children. But big questions remain on safety and ethics.

This year's flu season is hitting younger and middle-aged adults unusually hard, federal health officials say.

More than 60 percent of flu patients who ended up in the hospital this year have been between the ages of 18 and 64. The proportion of young people among the hospitalized is much ...

Here's possible solace for parents who are up at night with a baby who gets sick all the time: There appears to be a good reason why infant immune systems don't fight off germs.

A newborn's immune system is deliberately not doing battle with every germ that comes along so ...

After spending months working on a series of stories about the trillions of friendly microbes that live in and on our bodies, I decided it might be interesting to explore my own microbiome.

So I pulled out my credit card and paid the $99 needed to sign up for the ...

The next time you look in a mirror, think about this: In many ways you're more microbe than human. There are 10 times more cells from microorganisms like bacteria and fungi in and on our bodies than there are human cells.

Scientists increasingly think that these microorganisms have a huge ...

The Food and Drug Administration Thursday announced that it wants the federal government to impose tough new restrictions on some of the most widely used prescription painkillers.

The FDA said it planned to recommend that Vicodin and other prescription painkillers containing the powerful opioid hydrocodone be reclassified from a ...

Federal health officials are worried about an unusually high number of measles cases occurring in the United States this year.

There have been at least eight outbreaks so far this year involving 159 cases, the federal Centers for Disease Control and Prevention reported Thursday in its Morbidity and ...

The Food and Drug Administration today took another step toward restricting use of OxyContin and other powerful and often-abused prescription pain medications.

The move comes amid an emotional debate over so-called long-acting opioid analgesics. Federal health officials and others are concerned about the rising number of Americans who ...