An Iowa woman gave birth yesterday to what may be the world's first surviving set of septuplets, making medical history with the successful delivery of four boys and three girls.

All of the infants, born to Kenny and Bobbi McCaughey, were listed in serious condition after being delivered by Caesarean section at Iowa Methodist Medical Center in Des Moines; one, Joel Steven, was briefly listed as critical but later upgraded to serious. But doctors and family members seemed elated by the babies' apparently robust health and their birth weights, which ranged from 2 pounds, 5 ounces to 3 pounds, 4 ounces.

"I am probably one of the proudest grandfathers in the country at this moment," said Bob Hepworth, Bobbi's father, beaming as he announced the births. "I would ask that all believers across the world join us in praying for Bobbi and the babies."

Bobbi McCaughey, 29, had just entered her 31st week of pregnancy, short of the typical 40-week gestation period but well past the point where doctors believed the fetuses could survive. Generally, women expecting multiple births do not go the full term, and premature infants are most vulnerable to respiratory problems and feeding complications. But doctors said the McCaughey infants apparently were well developed and had benefited from pre-birth medication to strengthen their lungs. A team of 40 specialists attended the births, which took about six minutes, hospital officials reported.

"It was not chaotic," said Paula Mahone, an attending perinatologist. "Everybody in the room had a responsibility and they fulfilled that responsibility very well. We were all very excited as we delivered each baby and saw the nice size of the baby and how vigorous they were."

Karen Drake, another attending physician, said that the decision was made Tuesday night to deliver the babies yesterday after Bobbi McCaughey began having contractions.

"She had had it," Drake said with a smile at a televised post-birth news conference, "so we delivered." After the births, McCaughey was resting well, the doctors said.

The last septuplet birth in the United States, in 1985, involved a California woman.

In that case, one of the infants was stillborn, three others died, and the surviving three have battled a myriad of health and developmental problems.

In the McCaughey (pronounced McCoy) case, this was a moment that the world -- and the family's home town of Carlisle, population 3,500 -- had eagerly and nervously awaited. For months, residents of the town 10 miles southeast of Des Moines had carefully guarded the secret that Bobbi McCaughey was carrying seven fetuses, not wanting to unleash a storm of publicity.

The news came to light only at the end of October, when McCaughey reached her 28th week and much of the danger seemed past.

"We've been hanging in there -- we're so excited and so happy," said LaVena Owens, a Carlisle florist and family friend who knew about the pregnancy four months before the rest of the world. "This is the best news."

The McCaugheys, who met at a Bible college, already have a daughter, Mikayla, nearly 2, and it was their difficulty in conceiving her that led Bobbi to take the fertility drug pergonal. Septuplets do not occur naturally, and although the popularity of fertility drugs in recent years has increased the chance of such large multiple births, many doctors warn that they are best avoided.

"We all think it's wonderful that she's been successful, apparently, and we wish her well in the future," said Carl Weiner, director of the Center for Advanced Fetal Care at the University of Maryland School of Medicine. "But although this is a wonderful occasion, this is not the goal of fertility drugs. We should seek to avoid high-order multiple gestations whenever couples have a moral objection to selective fetal reduction."

Doctors in the McCaughey case raised the possibility of "reduction" -- aborting some fetuses to give others room to grow -- when they first detected the seven fetuses, but the McCaugheys, who are deeply religious, refused to consider the option.

"God gave us those kids and he wants us to raise them," Kenny McCaughey, 27, a billing clerk at an auto dealership, told local reporters last month in the only news conference he has given. McCaughey also had asked that reporters "be patient with us" and allow them privacy, and requested that no one send gifts until the babies' birth.

In Carlisle yesterday, residents were bracing themselves for a deluge of pink and blue presents -- and for another wave of reporters come to cover the unprecedented event.

The rumor mill in town cranked up yesterday morning with whispers that "this might be the day," said Brooke Wilson, who works at Wright Chevrolet with Kenny McCaughey and his father, Ken Sr. "We had an idea something was up when Kenny and his dad didn't show up for work."

Bobbi McCaughey, who had stayed in bed for much of her pregnancy, had been hospitalized since Oct. 15.

"Everybody is thrilled," Wilson said. "A bunch of people around here are smiling bigtime today." She added that folks around town were busy changing their outdoor signs from "Best wishes, Kenny and Bobbi!" to "Congratulations, Kenny and Bobbi!"

They are all eagerly awaiting the arrival home of the infants: Brandon James, Kenneth Robert, Nathan Roy, Alexis May, Kelsey Ann, Natalie Sue and Joel.

But, in the midst of the happiness, everybody also realizes that the biggest challenges for the young family have only just begun. "Someone has to win the lottery and really, that's what she's done," Weiner said. "But the birth is just the beginning of the story, not the end." CAPTION: Shown with her parents, toddler Mikayla McCaughey now has seven baby siblings. CAPTION: At present, the family lives in this house in Carlisle, Iowa, 10 miles from Des Moines. Kenny McCaughey is a billing clerk at an auto dealership.