Seven months ago, 26-year-old Linda Sanchez got the best and the worst of news. She was told she was pregnant with her first child and within days she was also told she had breast cancer.
Tonight, we will have an update on this incredible story of a cancer patient who refused to give up her baby. Watch "World News with Charles Gibson" tonight at 6:30 p.m. ET.
On Monday -- one month before her scheduled delivery -- Sanchez gave birth to a 5-pound, 2-ounce baby after being induced into labor Sunday. Sanchez needed only 15 minutes of pushing to give birth to Isabella, who measured 18 inches long.
The dark hair covering Isabella's tiny head was evidence that her mother's chemotherapy did not affect the baby's development.
Without an innovative new treatment for pregnant women with breast cancer, Isabella would have never had a chance.
Just months ago, a doctor presented Sanchez with an excruciating choice. She could either start chemotherapy and risk severe birth defects to her baby or delay treatment and risk losing her life.
"My doctor basically said it was me or the baby," she said.
The message was that Sanchez should consider having an abortion. It's the same advice many other women in this situation receive.
But pioneering research at the University of Texas MD Anderson Cancer Center has shown there's a better way -- that it's now possible to treat a woman's cancer without harming her unborn child.
"Yes, chemotherapy is toxic. But what we have found is that when given in the second or third trimesters it appears to be safe," said Dr. Jennifer Litton, breast oncologist at the MD Anderson Cancer center.
A specific "regimen" of chemotherapy used for pregnant cancer patients has enabled the births of dozens of healthy babies.
Amazingly, even when the chemotherapy can make a woman bald, her baby can be born with a full head of hair.
"[The] placenta is protecting the baby. That baby is not getting the same side effects as the mother," Litton said.
Over the next several months Linda had a series of chemotherapy sessions. And while she still needs more treatments and surgery after she gives birth, her tumor has already shrunk 60 percent.
"Oh, she's doing great. She's meeting all the milestones of any normal pregnancy," Dr. Mildred Ramirez of the University of Texas Medical School in Houston said in early November.
Isabella was due next month, but her birth was pushed up so that Sanchez could continue to receive cancer treatment next week and have surgery afterwards.
This afternoon, the Memorial Hermann-Texas Medical Center confirmed to ABC News that both mother and baby were healthy and ready to go home tonight for some well-deserved rest.
CHARLES GIBSON and JOHN McKENZIE contributed to this report.