Elisabeth Moss makes surprise pregnancy announcement on live TV: 'Are you pregnant or just an incredibly committed method actor?'

Handmaid's Tale star Elisabeth Moss confirmed she's pregnant and expecting her first child during an appearance on Jimmy Kimmel Live on Tuesday night (Wednesday AEDT).

The actress, 41, was dressed in black but did not disguise the baby bump as she spruiked her newest project, prompting a question from the US TV host.

"Are you pregnant or just an incredibly committed method actor?" Kimmel, 56, asked the star.

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"A little bit of both," she giggled in reply.

The heavily pregnant Mad Men actress said she's been "really lucky" so far during her pregnancy and "it's been going really well".

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The Top of the Lake actress then asked the father-of-four for tips in the delivery room, suggesting she's not got long to go before giving birth.

The comedian repeated some advice actor Bill Murray had offered Kimmel and his wife, TV producer Molly McNearney, before the birth of their first child.

"He said bring Christmas lights to hang up [in the delivery room], beads, a night light ... or a battery-operated candle" Kimmel recalled.

"The lighting is terrible in the room, it's like Walmart style lighting for this blessed event that is going to happen and you don't want that."

Other than confirmation that a baby is on the way, the actress, who is fiercely private about her personal life, didn't divulge any further details.

The two-time Emmy Award winner was previously married to Saturday Night Live star Fred Armisen for a year before the pair divorced in 2011.

She's previously been linked to cinematographer Adam Arkapaw but it's understood they split in 2015 after three years together.

Moss has spoken about her hopes of one day having her own kids after years spent playing Offred in the TV adaptation of Margaret Atwood's dystopian novel.

"I definitely want to have kids because I've been very inspired by the kind of mother my mum is. She did a beautiful thing with me," she said in a 2022 interview with YOU magazine.

In a 2018 chat with Marie Claire she said she'd come around to the idea of motherhood as she got older.

"It's not for everybody, and I didn't know if it was going to be for me, but lately, I think it is," she said.

"I have no idea how I want to do it though or what the plan is."