PRETORIA, South Africa (AP) -- Providing a powerful AIDS drugs to all HIV-positive pregnant women could spare the lives of thousands of children, lawyers for AIDS activists argued in court Monday.

Nearly 200 babies are born in South Africa with HIV every day, and studies indicate that the drug nevirapine could reduce that number by nearly half.

AIDS activists and hundreds of South Africa's pediatricians have sued to force the state to make nevirapine available through the public health system.

The German-based pharmaceutical company Boehringer Ingelheim has offered to distribute the drug for free, but the government says its safety has yet to be proven and has restricted its distribution to a handful of pilot sites.

Gilbert Marcus, the AIDS activists' advocate, called the state's position arbitrary, unreasonable and irrational, and said it amounted to a decision that could cause "potentially thousands of predicable but avoidable deaths of children."

Quoting government figures, Marcus said nearly 23 percent of pregnant women were HIV positive, yet only 10 percent had access to nevirapine.

"The impact of the policy is nothing short of tragic," he said in opening arguments at Pretoria High Court on Monday.

Nevirapine, which has the backing of the World Health Organization, has been used effectively to stop mother-to-child transmission of HIV in a number of countries.

But Marumo Moerane, a lawyer for the state, argued that the government must adopt a cautious approach in issuing the drug and ensure recipients that are adequately educated.

Despite being administered nevirapine, women were still transmitting HIV to their children through their breast milk, Moerane said.

"In order to give maximum benefits to pregnant women and children, you have to have phased implementation," he said. "We are trying to be responsible."

Judge Chris Botha asked why the state had not set targets and timelines for distributing the drug nationwide.

"It seems to me it (nevirapine distribution) has to be extended across the country as soon as is practically possible," Botha said, calling AIDS a national tragedy.

Earlier Monday, about 200 AIDS activists marched to the Health Ministry to demand improved access to medication, waving banners reading: "Save our babies" and "Government save us and our children" and singing, "Thabo Mbeki, what you are doing is not right."

President Mbeki has questioned the link between HIV and AIDS, saying poverty and malnutrition are also to blame for the spread of the epidemic.

Protesters laid white crosses etched with names of children who died of AIDS on the steps of the building before marching to the courthouse.

"People have lost their children because they didn't have the medicine," said Julia Matimulale, a 27-year-old AIDS activist from Soweto, a township near Johannesburg. "I don't want there to be any more children lost."

More than 4.7 million South Africans -- one in nine -- are HIV positive.