Britain's former prime minister Margaret Thatcher was in hospital Saturday recovering from a minor operation to remove a growth in her bladder and may remain there over Christmas, friends said.

The 87-year-old "Iron Lady", Britain's first and only female premier, was doing "absolutely fine" having been admitted to hospital on Thursday feeling unwell, her spokesman said.

A British judge ruled Friday that a seven-year-old boy with cancer can have radiotherapy treatment despite his mother's opposition.

New Zealander Sally Roberts, 37, had refused to give consent for her son Neon to receive radiotherapy to treat a brain tumor, fearing that it would cause him long-term harm and arguing that "credible" alternative treatment was available.

A U.S. court put on hold Friday a new Californian law banning a form of therapy designed to change the sexual orientation of minors, pending a further appeal.

The law barring doctors from performing so-called "reparative therapy" was signed by California governor Jerry Brown in October, and was due to go into force on Jan 4.

More than 3.5 million Pakistani children missed out on polio vaccination this week in a campaign overshadowed by the deaths of nine immunization workers, a U.N. official said Friday.

The Muslim-majority nation of 180 million people is one of only three in the world where the highly infectious, crippling disease remains endemic and infections shot up from a low of 28 in 2005 to almost 200 last year.

The Inter-American Court of Human Rights has struck down a Costa Rican ban on in-vitro fertilization, saying that its guarantee of protection for every fertilized embryo violated the reproductive freedom of infertile couples.

Reproductive rights groups said the decision late Thursday could have far-ranging implications for laws in many Latin American countries that ban all forms of abortion and some types of contraception. The decision explicitly states that not all embryos and fetuses are guaranteed complete protection, which the groups say will let them challenge laws that ban measures such as emergency contraception and abortion in cases of rape and danger to the mother's health.

Nelson Mandela's condition was serious when he was admitted to hospital 13 days ago, but the 94-year-old icon's health is improving, South African President Jacob Zuma said Thursday.

"His condition was serious but he is responding well to treatment and has steadily improved over the last few days," Zuma told members of the ruling African National Congress at the close of a party conference.

Venezuelan President Hugo Chavez is making steady progress after cancer surgery in Cuba and the respiratory infection he developed earlier in the week has been contained, aides said Thursday.

"He's well, he's conscious," said Vice President Nicolas Maduro, speaking to dozens of supporters at the swearing-in ceremony for the newly-elected governor of the central state of Guarico.

Surgeons in Zurich have carried out a complex, multi-organ transplant, hospital officials said Thursday, claiming the lessons learned would benefit patients with tumors that attack multiple organs.

Two teams of surgeons at the Zurich University Hospital had carried out a live liver transplant and simultaneously transplanted large blood vessels and replaced part of the same patient's heart with regenerated tissue, the hospital said in a statement, describing the operation as a "world first".

Three Palestinians in the West Bank have died in the past week from the H1N1 influenza strain known as swine flu, the Palestinian Health Ministry said on Thursday.

"There were three deaths in the past week, and more than 50 people sickened by the virus," Assad Ramlawi, the ministry's director general of health care for the West Bank, told AFP.

The head of the World Health Organization warned Thursday that infectious diseases will spread more easily in the future due to globalization, changing lifestyles and rising population densities.

"The future looks very bright for microbes, not so good for humanity," Margaret Chan told a luncheon in her hometown Hong Kong, the site of a major outbreak of the SARS virus in 2003 that killed almost 300 people in the city.