Madonna has reportedly been offering Britney Spears advice to guide her through her first pregnancy.

The mother-of-two, who has reportedly agreed to become godmother to the 23-year-old singer's firstborn, was only too happy to oblige when the "Toxic" star wanted an expert guide, reports Femalefirst.

"When Britney found out she was expecting, one of the first things she did was phone Madonna," a source said.

"Madonna has been sending books and offering advice about pregnancy to Britney almost daily."

The two celebrities have been friends since the "Material Girl" introduced Britney to the mystic Jewish faith, Kabbalah, over a year ago. Since then Madonna has been sending the young singer lavish gifts, including a 900-year-old Kabbalah book worth thousands of pounds as an engagement present.