At birth, Melinda Star Guido was so tiny she could fit into the palm of her doctor's hand. Weighing just 9 1/2 ounces - less than a can of soda - she is among the smallest babies ever born in the world. Most infants her size don't survive, but doctors are preparing to send her home by New Year's.

Melinda was born premature at 24 weeks over the summer and spent the early months cocooned in an incubator in the neonatal intensive care unit in Southern California. Almost every day, her 22-year-old mother sits at her bedside and stays overnight whenever she can.

The day before her Thursday due date, Haydee Ibarra visited Los Angeles County-USC Medical Center where her daughter has been since her birth in late August. Melinda is believed to be the second smallest baby to survive in the U.S. and third in the world.

Ibarra caressed Melinda through the portholes of the incubator where nurses pinned up a homemade sign bearing her name. Now weighing four pounds, Melinda gripped Ibarra's pinky finger and yawned.

During her pregnancy, Ibarra suffered from high blood pressure, which can be dangerous for both mother and fetus. She was transferred from a hospital near her San Fernando Valley home to the county's flagship hospital, which was better equipped to handle high-risk pregnancies.

There was a problem with the placenta, the organ that nourishes the developing fetus. The fetus, however, was not getting proper nutrition, blood and oxygen. Doctors knew Melinda would weigh less than a pound, but they were surprised at how small and fragile she was.

"The first few weeks, it was touch and go. None of us thought the baby was going to make it," said Dr. Rangasamy Ramanathan, who oversees premature infants.

Even if she survived, doctors told Ibarra and her husband Yovani Guido, children born this extremely premature can have developmental delays and impairments such as blindness, deafness or cerebral palsy.

Ibarra, who previously had a stillborn, told doctors to do whatever necessary to help her baby.

"They said, `We'll take the chance. Please try.' So we said.

'OK we'll try," Ramanathan recalled.

Melinda was delivered by cesarean section at 24 weeks and was immediately transferred to the NICU where a team of doctors and nurses kept watch around the clock. Infants born before 37 weeks are considered premature.

Melinda was kept insulated in an incubator and was hooked up to a machine to aid her breathing. She got nutrition through a feeding tube. Her mother said her skin felt like plastic because it was so thin.

"It takes a lot of good care and a lot of good luck. Most of them don't survive," said pediatrician Dr. Edward Bell of the University of Iowa who keeps an online database of the world's smallest surviving babies who were less than a pound at birth.

The list currently contains 126 babies dating back to 1936. Since submission is voluntary, it does not represent all survivors.

Ten babies weighing less than a pound were born last year and survived. Melinda joins three other tiny survivors delivered this year in Berkeley; Seoul, South Korea; and Iowa City, Iowa. All are bigger than Melinda, who is not eligible to be listed until she gets discharged.

Most tiny babies who survive tend to be female. That's because female fetuses mature faster than males of the same gestational age. Having more developed lungs and other vital organs increases odds of survival.