This month somewhere in sub-Saharan Africa the one millionth baby will be born without HIV to a mother who suffers from the disease, thanks in large part to a decade-old U.S. aid program.

It is yet another remarkable step in the long fight against HIV and AIDS, as the United States and its global partners work towards what they call an AIDS-free generation, which just a decade ago would have been unimaginable.

Pregnant women who were exposed to high levels of air pollution were twice as likely to have a child with autism as women who lived in low pollution areas, a U.S. study said on Tuesday.

According to experts at Harvard University, the research is the first large national study to examine links between the prevalence of pollution and the development of the developmental disorder.

Japanese experts were Tuesday set to discuss rules for experiments with animal-human embryos, as scientists seek permission for tests that could see human organs produced inside the growing body of an animal.

Researchers want to introduce a human stem cell into an animal embryo, to create a so-called "chimeric embryo", which they can implant into an animal's womb.

By the time 10-year-old Sarah Murnaghan finally got a lung transplant last week, she'd been waiting for months, and her parents had sued to give her a better shot at surgery.

Her cystic fibrosis was threatening her life, and her case spurred a debate on how to allocate donor organs. Lungs and other organs for transplant are scarce.

An Australian woman who now speaks with a French-sounding accent after a head injury eight years ago has revealed the experience has left her feeling frustrated and reclusive.

Leanne Rowe, born and raised on the southern Australian island of Tasmania, was in a serious car crash which left her with a broken back and jaw.

China's newly announced measures to combat pollution by slashing emissions from major polluting industries and holding local officials responsible could take 18 years to bring air quality within acceptable standards, analysts said Monday.

The problem of air pollution has stoked popular discontent across the country, with levels of particulate matter in Beijing measured at 40 times above World Health Organization limits this year.

The 10-year-old Pennsylvania girl who fought for a lung transplant has a difficult journey ahead. The transplant isn't a cure for her cystic fibrosis, and new lungs don't tend to last as long as other transplanted organs.

But it can extend life by years, buying some time.

Men and their preference for younger female mates may have led to the phenomenon of menopause in women, according to a controversial study by Canadian researchers published this week.

"If women were reproducing all along, and there were no preference against older women, women would be reproducing like men are for their whole lives," said evolutionary geneticist Rama Singh, a professor at McMaster University.

Four suspected cases of the human variant of mad cow disease, one of them fatal, have emerged in western Canada, local media reported Friday.

The degenerative brain disease Creutzfeldt-Jakob is so rare that it is odd for four suspected cases to crop up at once, CBC News quoted British Columbia Provincial Health Officer Perry Kendall as saying.

A review into the care of a pregnant Indian dentist who died after being denied an abortion in Ireland identified a number of failings when its conclusions were published on Thursday.

The death of 31-year-old Savita Halappanavar in October ignited calls for new legislation governing abortion in predominantly Catholic Ireland.