The Starbucks peppermint latte I’m sipping weighs nearly 3 oz. more than Rumaisa Rahman did at birth. The tiny twin, born in 2004 at Loyola University Medical Center weighing 9.2 oz., holds the record of world’s smallest baby. She unseated the previous title-holder, Madeline Mann, born 15 years earlier at 9.9 oz., also at Loyola.
Dr. Jonathan Muraskas resuscitated both babies, who are now 7 and 22. A Loyola professor of pediatrics and neonatal/perinatal medicine, Muraskas knows a thing or two about extremely low birthweight babies born the size of cell phones. And now he’s published a study in Pediatrics that looks at the girls’ outcomes several years down the road.
Amazingly, both micropreemies have reached appropriate developmental milestones in both motor and language skills. Rumaisa is a first-grader, and Madeline is an honors student at Augustana College in Rockland, Ill. They have thrived, but their stories should not be interpreted as the norm and could even “propagate false expectations for families, caregivers and the medico-legal community alike,” according to the research.
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Doctors are far from united on how young is too young to save. Earlier this year, I wrote about that gray zone:
Doctors in the U.S. often advise that premature babies born before 23 weeks be given only “comfort care” — swaddled, they’re handed to their parents to hold, free of medical interventions. If parents insist on treatment and the baby weighs more than 500 grams (about 17.5 ounces), “most of us give it a try,” says Gerri Baer, a neonatologist in Rockville, Md., who also happens to be my oldest friend.
Even though medical care has advanced considerably in recent decades, many premature babies suffer complications. More so than birthweight, it is in fact length of gestation that is considered the more significant determinant of survival and outcomes. While both Rumaisa and Madeline were undeniably tiny, they had had more time in the womb to allow their organs to develop — one was born at 25 weeks and the other at 26 — compared with other extreme preemies. The limit of viability is generally considered to be 23 weeks; a full-term pregnancy lasts 40 weeks. “It’s not how small you are, it’s how long you are in the oven,” says Muraskas.
Caring for preemies is far from an exact science, says Muraskas, and premature babies weighing more than Madeline or Rumaisa may not necessarily be saved. Rather than hail the girls’ survival as a miracle, both Muraskas and Dr. Scott Berns, a senior vice president at the March of Dimes, credit it to their gestational age.
“It’s incredibly wonderful how well these babies did,” says Berns. “But we’re still talking about a huge epidemic in this country where more than half a million babies are born each year preterm.”
In April, a preterm baby girl thought to be Europe’s youngest survivor went home from the hospital after being born at 21 weeks and five days. At just over 1 lb., Frieda Mangold weighed more than Madeline and Rumaisa, yet her long-term outcomes may be more uncertain. Babies born at 23 weeks and younger have about a 20% survival rate, says Muraskas, and up to 90% experience blindness, deafness or cerebral palsy. But babies born just one month later have about a 90% chance of surviving, with just a 5% chance of having devastating complications.
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Not only did Rumaisa and Madeline have relatively long gestations for their weight, but they also had the advantage of being girls, who have better survival rates than boys. Both mothers had preeclampsia — pregnancy-induced high blood pressure — and in anticipation of their early deliveries, they were given steroids before birth to help their infants’ lungs and brains mature. A study published last week in the Journal of the American Medical Association recommends giving steroids as early as 23 weeks to women at risk of delivering prematurely.
While the micropreemies managed to dodge the most serious effects of prematurity, both girls have retinopathy — eye damage caused by being born too early — and are small for their age. At 4 ft. 6 in. and 70 lbs., Madeline is particularly slight.
According to a registry curated by the University of Iowa, Rumaisa is the world’s smallest surviving baby — she and her twin, Hiba, are in the Guinness Book of World Records as smallest surviving twins — and Madeline is now the world’s fourth smallest survivor.
(The second and third smallest babies in the world were born in Germany and Japan, the latter of which has endorsed lowering the limit of viability to 22 completed weeks of gestation.)
Neither family wanted to speak to Healthland about their experiences, but Muraskas keeps in touch with them and shared two tidbits: Madeline calls him “Uncle Jon,” and Rumaisa’s mom recently delivered a healthy daughter who weighed a good bit more than her big sis.
Bonnie Rochman is a reporter at TIME. Find her on Twitter at @brochman. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.