Sen. Tammy Duckworth (D-IL) is about to become the first US senator to give birth while in office.

The Chicago Sun-Times’s Lynn Sweet reported Tuesday that Duckworth is expecting her second child in April, which will make her one of 10 other female lawmakers who have given birth while serving in Congress. But all of those women served in the House of Representatives when they had their children, including Duckworth herself, who had her first child as a representative in 2014.

Beyond being a milestone for the (mostly male and older) Senate, Duckworth, in her interview with Sweet, opened up about her struggles to get pregnant, including a miscarriage she suffered during her 2016 Senate campaign. Duckworth had her daughter at 47, while she was serving in the House, and her second child will be born shortly after she turns 50. “I’ve had multiple IVF cycles and a miscarriage trying to conceive again, so we’re very grateful,” Duckworth told Sweet.

Duckworth was first elected to the House of Representatives in 2013. She had previously worked in the Obama administration’s Department of Veterans Affairs. She served in the Iraq War in 2004, and lost both her legs after her helicopter was shot down. In 2016 she ran for an Illinois Senate seat, defeating Republican incumbent Sen. Mark Kirk.

Sen. Kirsten Gillibrand (D-NY) is the only other current senator to have given birth while in office, though her second son was also born, in 2008, while she was a member of the House. Duckworth took 12 weeks of paid maternity leave in 2014-’15, according to Roll Call, the same amount she offers her staff.