The Spice Girls are under pressure to increase their world tour to 50 dates, after an unprecedented demand for tickets from fans.
The band - Victoria Beckham, Mel B, Emma Bunton, Mel C and Geri Halliwell - are to hold talks with manager Simon Fuller to extend the tour after two million fans registered on the group's website.
However, the group - who have agreed to 11 dates and are already considering a further 14 shows - are said to be reluctant because of family commitments.
A source said: "The girls really want to do a huge tour but they're worried about how much they'll be able to commit to it because of their families."
Victoria - who has just moved to Los Angeles with husband David - has three sons, Brooklyn, Romeo and Cruz, and Mel B has two daughters, Phoenix Chi and Angel Iris.
Geri is mother to one-year-old Bluebell Madonna, Emma is due to give birth next month, while Mel C has just got engaged and has solo commitments.
A Spice Girls spokesman said: "The interest has been unprecedented. We believe there have been enough ticket applications to fill London's new Wembley Stadium 20 times over!"
The band - who will also release a greatest hits album to coincide with the tour this December - announced last month they were reuniting - seven years after their last album was released. | 
