According to The Sun, the One Direction star asked to meet with Eleanor in LA to break the reported pregnancy news himself.
A source told the newspaper: "She was blinded by the news and is still trying to get her head around how everything has changed so fast. But she appreciates he had the decency to tell her in person. He did the right thing."
Another source told People: "Eleanor knows and she's fine."
So far, reps for Louis have not confirmed the reports that he's expecting a child with US-based stylist Briana Jungwirth.
People magazine and The Sun have both claimed Louis and Briana enjoyed a few dates back in May after meeting via mutual friends. Louis had split from Eleanor around March.
While Louis and Briana are not together in a relationship, they have stayed friendly. Reports claim Louis has told Briana he wants to be fully involved in the pregnancy and has even accompanied her to baby scans.
It's also believed Louis and Briana's families have met and are excited about the new arrival.
Eleanor is thought to be in the US right now celebrating her birthday with friends, while Louis is in the US on the North American leg of One Direction's latest tour.