Meghan Trainor Reveals the Song She Wishes She Never Gave Away — Hint: It Went to a Girl Group

Meghan Trainor has written hits for several other musicians, but it turns out there's only one she wishes she would've kept for herself.

The "Made You Look Singer," 29, revealed in an interview with PopCrush published Tuesday that the one song she wrote that she regrets giving away is "Sledgehammer" — made famous by former girl group Fifth Harmony.

When asked which of her compositions she'd like to reclaim, Trainor answered by busting out the first line of the tune: "If you could take my pulse right now."

"'Sledgehammer' by Fifth Harmony is such a great one," she clarified.

"Sledgehammer" is the second single from the group's debut album, Reflection. Trainor shares writing credits on it with Jonas Jeberg and Sean Douglas.

The song earned Fifth Harmony their first top 40 Billboard Hot 100 entry in the U.S., and it was eventually certified platinum.

Apparently, "Sledgehammer" is not only simply a banger, but also holds sentimental value for Trainor.

She told PopCrush that she believes writing the song for Fifth Harmony was the first time she "really impressed" her husband, actor Daryl Sabara, since it was the Spy Kids star's love for the girl group that solidified to Trainor that they were "soulmates."

The pop star is expecting her second baby with Sabara, 30, she confirmed to PEOPLE on Monday.

"What a blessing," Trainor told PEOPLE exclusively. "I'm just so grateful I can get pregnant. And I'm like, 'I'm crushing it. This is amazing. This is my dreams.' I'm halfway there — I want four kids!"

Trainor and Sabara are already parents to son Riley, whom they welcomed in February 2021.