X-ray of Lyna Gonzalez' mouth tumor before in utero surgery to remove it. (Source: Jackson Memorial Hospital)

MIAMI (CBSMiami) – To see 20-month old Lyna Gonzalez, you would think she’s just like every other toddler at that age – vibrant and energetic.

“She’s perfectly normal, thank God,” said mother Tammy.

But it wasn’t always that way. During her pregnancy, Gonzalez’s doctors discovered a benign tumor the size of a tennis ball growing on her unborn baby’s mouth. Doctors told Tammy there was little chance her daughter would survive birth – and if she did, she would require an immediate tracheotomy in order to breath and have multiple surgeries thereafter.

“It’s the most horrible feeling you could ever image; physically, emotionally, mentally,” said Gonzalez.

After a lot research and heart ache, Tammy sought help from University of Miami/Jackson Memorial fetal surgeon Ruben Quintero.

Quintero, a pioneer in fetal medicine, has treated many birth defects and high risk conditions while the baby is still in the womb.

“The concern with these tumors is they grow very rapidly, the cause bleeding which leads to the death of the baby,” said Quintero.

In May 2010, Quintero and Dr. Eftichia Kontopoulos operated on Tammy’s baby in utero. Using an endoscope guided by ultrasound they performed a first of its kind surgery and removed the tumor from the fetus’ mouth.

“This was an opportunity to expand the field we have developed, to treat birth defects in utero,” said Quinero.

The surgery was performed in the 17th week of the pregnancy and Tammy, who was under local anesthesia, was awake during the procedure.

“I could see it floating down,” said Gonzalez. “It was like this huge weight had been lifted off. It just floated away and I could see her face.”

Quintero said these types of oral tumors develop in 1 and 100,000 pregnancies.

On October 1, 2010, Leyna Mykaella Gonzalez was born healthy, weighing 8 pounds, 1 ounce. The only sign of the surgery is a tiny scar on her mouth.

This case was recently published in the American Journal of Obstetrics and Gynecology as the first of its kind.