At 18 weeks pregnant, she faced an immense decision with just days to make it

In April, Karla Renée got a surprise positive on a pregnancy test. She and her husband Sam had tried unsuccessfully to get pregnant before and had expected they'd need fertility treatments.

"For it to just happen naturally felt like a miracle," she says. "We were ecstatic."

By the time she found a doctor in her insurance network near where she lived outside of Raleigh, N.C., and got in for her first appointment, she was eight weeks pregnant.

"The doctor noted that since I'll be 35 when the baby was due, I should take a screening test for genetic anomalies," she says. "We agreed to do the test and we scheduled our next appointment for a month out."

For those few weeks, they were just "blissfully pregnant," she says.

At the 12-week appointment, the doctor noticed something called increased nuchal translucency in the ultrasound. This happens when extra fluid accumulates behind the neck of a fetus. "We'd never heard [of] that before," says Karla. "She explained that lots of babies have this and they can recover on their own, but it could be an indication of something more serious."

The first genetic screening results, from blood tests, came in — they were negative for several common genetic conditions. That test also told them they were having a girl. "We felt relief and we felt hope, and we started to call her Amber," Karla says.

Their ob-gyn recommended a second, more comprehensive genetic test – amniocentesis – to see if there was a cause for the fluid accumulation she'd observed on the