Saturday Night Live cast including pregnant Tina Fey reveal show`s secrets

American TV channel NBC's weekly sketch show has been running for 36 years and has catapulted some of the biggest names in comedy to global stardom.

First up was former head writer and host of Weekend Update, Tina Fey.

Tina, who is expecting her second child, has also recently become an author.

Tina explained to Oprah Winfrey about being pregnant again: 'You get to 40 and you think 'do I really want to do it, or is it because I'm running out of time?'

'Also, I thought 30 Rock would be cancelled by now and I'd have time to do it.

'My husband and I decided that, rather than risk having the show end in several years and feeling like part of our family was missing, that we were going to prioritise a family.'

Tina also said the title of her book, Bossypants, came from a brainstorming exercise with her husband.

She said: 'I was trying to think of words that he associates with me, and all these words were like, 'bossy,' 'grouchy,' 'sour.'

'I was like, 'oh, brother... Bossypants' was the friendliest one'.'

In Bossypants, Tina addresses the nature of being a powerful woman in the generally male-dominated world of comedy.

Oprah's other guests were original Not Ready for Primetime Players Chevy Chase and Jane Curtin, impersonation hotshot Dana Carvey, and the hilarious Tracy Morgan.