"All kidding aside, for everyone going through infertility and conception hell, please know it was not a straight line to either of my pregnancies," she added. "Sending you extra love."
Hathaway already has one son, 3-year-old Jonathan Rosebanks, whom she shares with husband Adam Schulman.
Despite keeping her family mostly out of the spotlight, Hathaway recently made headlines with her statements regarding alcohol and parenting.
The actress says she's stopped drinking after becoming a parent.
"He's getting to an age where he really does need me all the times in the morning," she said on Ellen in January.
"I did one school run where I dropped him off at school, I wasn't driving, but I was hung over and that was enough for me, I didn't love that one."
