The 35-year-old former Spice Girl - who already has 12-year-old Phoenix Chi and three-year-old Angel Iris from previous relationships - is expecting her first baby with her husband Stephen Belafonte this summer and has revealed the pair are thrilled with the news.
Mel - who has been married to Stephen for three-and-a-half years - said: "We`re really excited. We wouldn`t have planned and waited for four yours to have a baby if we weren`t really excited about it and ready for it. Even though you can never really be truly ready."
When Mel broke the news to Stephen - who also has a six-year-old daughter, Giselle, from a former partner - he toasted the news with a glass of champagne, the last drink Mel will have before she has the baby.
Stephen said: "I promptly got a bottle of Cristal champagne and said, `Baby, enjoy this glass because you can`t drink anymore!` I must tell you, she really enjoyed that glass of Cristal."
The singer-and-fitness icon also revealed they are not yet sure if they want to know the sex of the child.
She added to Britain`s HELLO! magazine: "I haven`t fully decided if I want to know or not. I`m over the first trimester, so I`m past the shady three months and on to safe territory. The first three months, I was pretty sick and tired, to be honest, which I`ve never been before."
Just last week, Mel - who along with Victoria Beckham and Emma Bunton is the third Spice Girl to currently be expecting - revealed she planned to be pregnant by the end of 2011 because she "loves" having kids.
She said: "I`m always broody. Hopefully, I`m going to be pregnant by the end of this year, or, if not, next year. I love kids."