Last year, one of every eight babies born in the United States was premature, a number that is growing because of an increase the use of in vitro fertilization and other reproductive advances.
But the medical triumphs that allow a tiny 10-ounce baby to survive are often fraught with trauma and tragedy.
Consider this: At 25 weeks gestation or younger, a tiny baby can fit in the palm of a hand. Its skin is gelatinous -- red and shiny and prone to infection like a burn victim -- and sloughs off in the doctor's hand. The baby's windpipe is so small it can be crushed by a breathing tube.
And there is the pain, treated with narcotics that can cause dependency and withdrawal symptoms.
The long-term prognosis for babies this young includes mental retardation, blindness, deafness, cerebral palsy and — in the best scenario — learning disabilities.
Just Monday, Amillia Taylor — born at just 21 weeks and six days — suffered a setback after she was nearly ready to head home from Baptist Children's Hospital in Florida at a plump 4 pounds and 25 inches long.
Amillia is perhaps one of the world's smallest surviving babies -- although doctors say her age was determined by the day of conception (she was an IVF baby), rather than the conventional method of using the date of the mother's last menstrual period, making her actually two weeks older.
Still, even at 23 weeks of life, she is at a controversial crossroads, one week younger than the age at which a fetus can be legally aborted. Born just past the halfway point in a normal 37- to 40-week pregnancy, Amillia faces a likely struggle with health and learning problems.
"These babies survive, but they are extremely impaired," said Dr. Robert J. Boyle, professor of pediatrics at the University of Virginia's Center for Biomedical Ethics. "To do all of this for tiny babies takes a long time. From the time they are born until they go home, they go through a lot. How much do you subject a baby to, and what is the cost -- and I am not talking money -- in terms of discomfort."
In 2005, 12.5 percent of births in the United States were preterm or less than 37 weeks gestation, costing $26 billion a year, according to the National Institute of Medicine of the National Academies.
The number of babies born prematurely has dramatically increased in the last 20 years because of fertility treatments including IVF and fertility drugs like Clomid. The resulting infant death and long-term disability poses a serious public health issue, says the Institute.
A database run by the University of Iowa's Department of Pediatrics lists seven babies born at 23 weeks between 1994 and 2003, still a small number. Without extraordinary care, most of these babies die. But in the 25-week age group, about 50 percent survive.
"The incidence of these babies being born and entering the neonatal realm has increased; 20 to 30 years ago they never left the delivery room," said Dr. Boyle. "There are more of them overall now, and we take care of them."
Guidelines established by the American Academy of Pediatrics and the American Heart Association do not oblige a doctor to resuscitate an infant under the age of 22 weeks or one that weighs less than 400 grams -- or about a pound.
But with older babies "there needs to be an active discussion between parent and doctor," said Dr. Boyle.