In a few weeks, the first shipments of the H1N1 flu vaccine will arrive in Minnesota, and Stephanie Pelach, who is six months pregnant, will have a decision to make.

Should she get a vaccine, approved only weeks ago, that has never been tested in pregnant women? Or take her chances with a flu strain that can be especially dangerous during pregnancy?

For Pelach, who lives in New Brighton, it's a sobering choice. "There is this slight concern -- is this safe for me, is this safe for my baby?" she said. "I wasn't expecting it to be this emotional of a decision."

Health officials say that pregnant women should be among the first to get the new vaccine.

But they know it will be an uphill battle persuading some people -- even those who are at high risk -- to take it.

"With vaccines, you're asking a currently healthy person to do something to prevent a future harm," said Dr. Greg Poland, a Mayo Clinic expert in pandemic flu and infectious diseases. "To me, it's an easy decision. But I recognize not everybody would feel that way."

Many major medical organizations, such as the American College of Obstetricians and Gynecologists, are urging pregnant women to get the shots. Experts say the vaccine for H1N1 -- also known as swine flu -- is basically a variation on the seasonal flu shots that have been used for decades, made by the same manufacturers, using the same processes.

But advocates are running into something of a cultural backlash from those who believe that the vaccine is unnatural, unnecessary or unsafe.

"I won't get the swine flu vaccine and I won't give it to my kids," said Heather Lenort, of Plymouth, who is pregnant with her third child. Lenort, 34, said she is dubious about vaccine safety in general, and thinks this one is simply too new and untested.

"I feel like there hasn't been enough history of the side effects that it might cause, not only to me but the unborn baby," she said.

LeeAnn Heidt, 33, of Wayzata, who is expecting her third child in February, said she prefers to "build our immune system naturally," using herbal remedies and organic foods. She, too, thinks there is too little known about the vaccine. "Right now," she said simply, "I would not get this."

To some extent, pregnant women have always been leery of flu shots. Studies show that only about 15 percent get them in ordinary years, Poland said.

But this is no ordinary year. The global pandemic has raised the stakes, spreading flu far and wide and hitting pregnant women, and a few other groups, harder than most.

One of the first in this country to die of swine flu was a 33-year-old pregnant woman in Texas.

Disproportionate deaths

Since the outbreak started in April, scientists have noticed a pattern: A disproportionate number of expectant mothers have been hospitalized with the flu. So far, pregnant women, who make up 1 percent of the population, have accounted for 6 percent of H1N1 deaths, according to the federal Centers for Disease Control and Prevention in Atlanta.

Poland said that it is not clear why pregnant women are more vulnerable; it could be because of changes in their immune systems. But the numbers show that flu not only endangers their lives, he said, but increases the risks of miscarriage and birth defects as well.

Yet when it comes to vaccines, Poland said, mathematical probabilities are often no match for gut feelings.

"Some people will overvalue the teeny risk of a side effect," he said. "For some people, they will say, 'If I did something and it caused something [bad to happen], I would never forgive myself.' "

In this case, critics note that the vaccine was rushed into production with a few weeks' testing. None of it was done in pregnant women (though several studies are underway). In fact, the package inserts on the vaccines approved by the U.S. Food and Drug Administration (FDA) all share the same warning: "Safety and effectiveness ... have not been established in pregnant women [or] nursing mothers."

The FDA approved the vaccines for pregnant women based in part on the safety records of previous annual flu shots, which are developed the same way.

Poland said that, by fast-tracking the approval process, the government made some trade-offs.

"You're not going to have as much safety information as you would [like]," he said. "On the other hand, if you insisted on having that much safety [data], you would not have a vaccine until the following year or two. It's a bit of a dilemma."

Even with all the uncertainties, some predict that more pregnant women than ever may be lining up for flu shots this fall.

"It's certainly on the minds of our pregnant patients," said Dr. Charles Hirt, an obstetrician-gynecologist with the Paul Larson clinic in Edina.

With swine flu all over the news, he noted, they know the risk and they're eager to protect themselves. "Yes, they have their concerns, but if you can appropriately educate them, I think you can motivate them," he said. "It's quite clear that the group that gets vaccinated is going to be much less likely to be hospitalized and [will have a] much lower death rate."

Dr. Lori Wilcox of Oakdale Obstetrics & Gynecology in Robbinsdale agrees. "We're just trying to raise awareness ... and get as many of our patients vaccinated as we can," she said. "I don't think it's going to be a hard sell. I hope I'm right."

Maura Lerner • 612-673-7384