Many of Anna's fans and followers congratulated the new mum, remarking that it's a tough moment for many first-time parents.
"Well done! It’s a big step xxx" wrote TV personality Jess Rowe.
"Well done, babe! First big hurdle cleared xxx," Sunrise's Jessica Ridley penned.
"Congratulations! All those firsts can be daunting. You got this!" wrote another follower.
Throughout her pregnancy and first few weeks as a mum, Anna has kept it real with her social media followers.
During her third trimester, the season one Bachelor winner confessed: "It’s definitely been a love/hate relationship with my body whilst pregnant but I’m getting there."
Anna also confessed that ahead of Elle's birth, she was feeling a mix of emotions about becoming a mum.
"Feeling excited and nervous as all hell," she wrote.
New mum Anna may be all loved-up with her baby girl, but there is one family member who is still yet to meet Elle.
Younger sister Charlotte Heinrich is currently living overseas and won't be back in Australia until February 2021.
Taking to Instagram, Anna shared a throwback photo of herself and Charlotte in 2017 and remarked that she misses her little sis "every day."
"Three years ago today in Hong Kong. How times have changed," Anna captioned the photo.
"Can’t wait to see you again @charlotteheinrich (hopefully sometime next year). Miss you everyday. Elle can’t wait to meet you too. #AuntyCharlie #weallmissyou"