Music
The 18-year-old from Essex - real name Victoria Lott - becomes the first British solo female to debut in the top spot without first appearing on a reality show.
Last month the singer told DS that 'Mama Do' was "about sneaking out the house and going to see a specific person without your parents knowing about it".
Black Eyed Peas slip to two with 'Boom Boom Pow', while Agnes bounces back to three with 'Release Me'.
Meanwhile, French DJ David Guetta debuts at seven with 'When Love Takes Over', a collaboration with former Destiny's Child singer Kelly Rowland.
Outside of the top ten, Lady GaGa zooms from 43 to 13 with 'Paparazzi', while Jordin Sparks enters at 21 with 'Battlefield'.
The top ten singles in full (click for our reviews):
1. (-) Pixie Lott: 'Mama Do'
2. (1) Black Eyed Peas: 'Boom Boom Pow'
3. (4) Agnes: 'Release Me'
4. (2) Dizzee Rascal ft. Armand Van Helden: 'Bonkers'
5. (5) Daniel Merriweather: 'Red'
6. (6) Keri Hilson ft. Kanye West & Ne-Yo: 'Knock You Down'
7. (-) David Guetta ft. Kelly Rowland: 'When Love Takes Over'
8. (3) Kasabian: 'Fire'
9. (9) The Veronicas: 'Untouched'
10. (7) Soulja Boy ft. Sammie: 'Kiss Me Thru The Phone'
> Click here for this week's top ten albums
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