The earliest premature baby to survive after delivery is now a healthy toddler. 

The infant girl, who wasn't named because of family wishes, weighed less than a pound (410 grams), when she was born in San Antonio, Texas, in 2014. The baby's mother, Courtney Stensrud, was 32-years-old at the time and only 21 weeks and 4 days pregnant. Before her 20-week routine ultrasound, her pregnancy was moving along normally. It was during that checkup, her OB-GYN saw that her cervix was shortening. From there, she was in an out of the hospital and ultimately placed on bed rest before her daughter's birth.  

At birth, her daughter's skin was so thin, it was nearly see-through, Kaashif Ahmad, a MEDNAX-affiliated neonatologist at the Pediatrix Medical Group said. Ahmad was called into the delivery room a few minutes after the baby was born. Stensrud said her daughter faintly cried and moved when she came out, but Ahmad said the infant wasn't breathing when he arrived. 

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Any baby born before 37 weeks is considered premature. A baby born before 25 weeks is considered extremely preterm and often comes into the world with complicated medical problems, according to Mayo Clinic

In these situations, doctors don't recommend resuscitation. But, when Stensrud looked at Ahmad through tears and asked him to try, Ahmad did.

"If you’d like us to try, I’m willing to try," Ahmad said.

When doctors placed a breathing tube into her airway, the baby that was once blue turned pink, Ahmad said. 

"I’m very happy I did that," Ahmad said. "She’s a wonderful, beautiful little girl."

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The girl is now 3-years-old and doing well in preschool, on par with her peers. 

"She’s a little smaller in stature next to the other kids, but otherwise, she has no mental or health disabilities, or issues whatsoever," Stensrud said of her "miracle" daughter. "She is just normal."

Ahmad, lead author on a study published in Pediatrics about the girl's development, said the girl's situation shouldn't serve as an example of premature health at 21 or 22 weeks gestation, because more research needs to be done. 

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