FARGO (AP) - Medical advances have lessened but not erased all the risks women face in childbirth. On average, health officials say, one woman in North Dakota dies of complications of pregnancy or childbirth every year.

The state rate of maternal deaths has been consistent for several years, said Dr. Dennis Lutz, chairman of the obstetrics and gynecology department at the University of North Dakota medical school.

Between 8,000 and 9,000 babies are delivered in the state each year.

Lutz also heads a state committee that reviews the records of any woman in North Dakota who dies within a year of being pregnant.

"It's so unexpected and it's always a tragedy," he said. "Most of the time we don't have a problem, but we don't take for granted that childbirth is safe and that we never have to worry about the mother."

A hundred years ago, women in the United States were vulnerable to the hemorrhage, infection after delivery and high blood pressure, Lutz said.

In 1925, there were 95 maternal deaths in North Dakota.

"Since then, we've seen a tremendous decline, and we keep trying to get that rate lower," Lutz said.

Pregnant women today may die of blood clots, tubal pregnancies, complications from anesthesia or heart conditions, Lutz said.

"We can't eliminate 100 percent of risks," he said. "We are as vigilant as possible, but sometimes deaths aren't preventable."

Early prenatal care and sharing health issues or previous problems with a health professional can reduce the risks, he said.

The U.S. maternal mortality rate rose to 13 deaths per 100,000 live births in 2004, according to the National Center for Health Statistics - the second time the maternal death rate rose above 10 since 1977.

Researchers say the increase could be linked to better record-keeping or a rising Caesarean section rate, which comes with risks related to anesthesia, infections and blood clots.

Mark Peterson's wife, Lisa, slipped into a coma after suffering a heart attack during a Caesarean section in 2000. She now receives care at a small nursing home in Moorhead, Minn., and does not recognize her husband or 7-year-old son.

"It screws up your faith and everything else," Mark Peterson said. "There's nothing in the world that could prepare you for it."