(CNN) - Sen. Tammy Duckworth, who is expecting her second child while in office, opened up Thursday about the struggle facing professional women who want to raise children.
"My gynecologist at the (Veterans Affairs) facility actually, when I first started this over 10 years ago trying to conceive my first child, said, 'You know, so many of us professional women give up our fertility -- our fertile years -- in exchange for our profession, and that needs to change,' " the Illinois Democrat told Erin Burnett in her first interview with CNN since sharing her pregnancy news.
"Well, I want people to know that it is a journey, that it is a long process," Duckworth said.
The senator said her doctor assured her at the time that it's not unusual for her to be 42 years old and trying to conceive.
"And unfortunately, that's what families are facing all over this country, and so I wanted to make sure that Americans understood that this is a journey, we can get there and we need to support families," Duckworth said.
She announced Tuesday that she's expecting her second child in April. She had her first in 2014, when she was serving in the House of Representatives. She will be the first sitting US senator in history to give birth while in office.
When asked what the milestone means to her, Duckworth said, "It makes me a better senator."
"Having my first daughter, Abigail, when I was a member of the House of Representatives really taught me a lot of things about what working families face across this country," she said.
Duckworth is a first-term senator and a retired Army lieutenant colonel who was a helicopter pilot in the Iraq War. She was the first female double amputee from the war after suffering severe combat wounds when her Black Hawk helicopter was shot down. After retiring from the Army, she was elected to Congress in 2013.
Tune in at 7 p.m. ET for the full interview on "Erin Burnett OutFront."
Correction: This story has been updated to note that the interview was Duckworth's first with CNN since announcing her pregnancy.