Cesar Algeciras often spends five hours straight in the neonatal intensive care unit, lovingly clutching his premature son to his bare chest, a form of Kangaroo care.
"Feeling his heart beat is a delight," said the 36-year-old computer engineer. "Sometimes I don't even have to check the monitor to make sure he's fine."
This simple practice of skin-to-skin contact is known as "kangaroo care" -- in a nod to the marsupials who carry their young in a pouch after birth to complete their development -- and started in Colombia more than 30 years ago due to a shortage of incubators.
After an initial bout of skepticism, it has become common practice in this South American country -- and has spread around the world.
At just 27 weeks, Algeciras's son is one of several early-term newborns in the hospital struggling to survive.
And, while he does spend some time in an incubator, his father is convinced the physical contact is working wonders.
That's also the belief of Nathalie Charpak, the doctor who has pushed to standardize "kangaroo care" since 1978.
"An infant in intensive care doesn't sleep for more than 19 minutes at a time," she told AFP. "It's really traumatizing to be frank, it's torture."
- As effective as incubators -
While it sounds easy enough, "kangaroo care" comes with certain rules.
Parents are not allowed to change position -- except to feed and change the baby. And even at night, they can't lie down to ensure the infant stays upright and in constant contact with their skin.
The surrounding environment is also key. In an effort to recreate womb-like conditions, nurses at San Ignacio ensure the lights are dimmed and are alerted if the noise level rises above 60 decibels.
The practice -- which Charpak claims is "as effective as an incubator" -- has gained traction abroad.
"We have trained more than 30 countries," she said -- including the United States, Spain and Sweden.
Colombian doctors have also traveled to Asia and Africa to spread the word.
The effort seems to have paid off and has quite a following.
In 20 years, Brazil has reduced infant mortality by two thirds for those under five through a program partly consisting of "kangaroo care," according to UNICEF, the United Nations children's agency.
A study of Swedish mothers published by the US journal PubMed in 2011 showed that while participants considered the method exhausting, none gave up.
- Cultural barriers -
Initially considered an "alternative for the poor," the practice was given a boost by the World Health Organization in 2004 when it recognized it as a way of promoting breast feeding and stimulating a child's cognitive development.
Premature birth remains the leading cause of infant mortality in the world, where one in 50 babies die before they turn a month old, according to WHO figures.
Despite the benefits of "kangaroo care," cultural barriers continue to keep some people at bay.
That's especially true in India or Africa or "when the mother returns home, it's to work," Charpak said.
Reluctance has also come from doctors, in particular in developed countries where there may be an unwillingness to accept a method "that comes from a southern country," she added.
But at San Ignacio, where the "Kangaroo Foundation" is headquartered, parents like Algeciras certainly believe in the technique.
On any given day some 30 mothers can be seen hugging their tiny offspring -- wrapped up and wearing wool beanies -- to their hearts.