'It was just bad timing,' the actor said in an interview on Monday.
John Stamos was apparently in the mood for some candid confessions on Monday.
In an interview on Howard Stern's SiriusXM radio show, Stamos opened up about his struggles with addiction, his "terrible game" when it comes to women, and why Mary-Kate and Ashley Olsen passed on participating in Netflix's Full House reboot. But the most surprising tidbit was Stamos' revelation that he impregnated a mystery woman in his late 20s.
Asked by Stern whether he'd ever gotten a woman pregnant, Stamos admitted that he had and that the woman got an abortion.
"I'm careful and I have been careful," he said. "This was just bad timing. It really wasn't my choice ... I think it was sort of a mutual decision."
The 52-year-old star also revealed that he was "embarrassed" by his DUI arrest last year, which served as the catalyst for entering a rehab facility for substance abuse.
"I could have hurt somebody. It was really stupid and ignorant of me and I hated myself for that," he said. "It was time to go."
Stamos said that kicking his alcohol consumption was not a problem, but sleep aid Ambien proved a tougher addiction to beat.
READ: John Stamos Gets Candid About Rehab
"I'm so happy to be off that," he said. "[Ambien is] super dangerous. ... My memory was starting to get really f**ked up too from that. ... [It was] difficult to memorize scripts, I couldn't remember names and faces and things. That was the hardest thing to kick, by the way. Booze, that happened. Ambien was tough."
Stamos, who says he is now completely clean and sober, is returning to the role that made him a household name in the late '80s: Uncle Jesse. Netflix's Fuller House premieres on Feb. 26 with several key cast members returning, though the Olsen twins have famously passed on the project.
"They seemed very into it, they just were afraid of acting," Stamos told Stern. "They hadn't acted -- they don't consider themselves actresses. ... I said, 'Maybe you guys will just be here in New York and we'll do a phone call or something.' And they said, 'Let us think about it,' and it just wasn't for them. ... It's not about the money."
PIC: John Stamos Congratulates Mary-Kate Olsen on Her Marriage With Adorable Throwback
Stamos made headlines last month with a swoon-worthy Paper magazine photoshoot, showing off his bare bum! See the pics below.