Claire Danes struggled to keep her pregnancy a secret from her 'Homeland' co-stars because she kept accidentally falling asleep in between her takes on set.

The 39-year-old actress has just announced that she's expecting her second child with her husband Hugh Dancy but she has admitted the first trimester was a struggle for her because she felt so ''rotten'' and couldn't keep her eyes open during filming.

Speaking on 'The Tonight Show Starring Jimmy Fallon' on Wednesday (18.04.18), she said: ''I was filming during the first trimester which is kind of my least favourite phase because you just feel horrible. You feel just rotten and you're not allowed to say why. I was filming quite a lot but just inadvertently falling asleep all the time. And it was embarrassing. This one particular nap, I face-planted onto this crocheted bag in-between takes. It was time for my close up ... and I sit up and I have this crocheted indentation on the side of my face. It looked like I had third-degree burns.''

The blonde beauty plays bipolar disorder-stricken investigator Carrie Mathison in the CIA drama but has revealed she will be leaving the show after the eighth series.

Asked about rumours the next season will be the last, Claire - who can currently be seen on screen in season seven - told Sirius XM DJ Howard Stern: ''Yeah, that's it.''

Although she feels ''ready'' to leave, she is ''really conflicted'' about her departure.

She explained: ''I mean, I'll be ready. She's a lot, this Carrie-freakin' Mathison character. It's a workout, so I'll be ready for a reprieve from that.''

Claire and Hugh - who got married in 2009 after meeting on set of 'Evening' in 2006 -already have five-year-old son Cyrus together and are excited about meeting their new addition, whose sex they're keeping a secret, over the next coming months.