The piano line was taken from Johnny Parker's riff on Bad Penny Blues, a 1956 hit in Britain for the jazz trumpeter Humphrey Lyttelton, which had been produced by George Martin. "We asked George how they got the sound on Bad Penny Blues," said Ringo. "George told us that they used brushes. So I used brushes and we did a track with just brushes and piano and then we decided we needed an off beat so we put an off beat in." Lyttelton didn't mind at all, as he had taken the riff from Dan Burley anyway. "You can't copyright a rhythm, and rhythm was all that they had borrowed," he said. "I was very complimented. Although none of the Beatles cared for traditional jazz, they all knew and liked Bad Penny Blues because it was a bluesy, skiffley thing rather than a trad exercise."

Lady Madonna was intended by Paul to be a celebration of motherhood which starts with an image of the Virgin Mary with her child but then moves on to consider all mothers. "How do they do it?" he asked when interviewed by Musician in 1986. "Baby at your breast — how do they get the time to feed them? Where do they get the money? How do you do this thing that women do?"

American singer Richie Havens remembered being with Paul in a Greenwich Village club watching Jimi Hendrix perform when a girl came up to him and asked whether Lady Madonna had been written about America. "No," said Paul. "I was looking through this African magazine and I saw this African lady with a baby. And underneath the picture it said "Mountain Madonna". But I said, oh no — Lady Madonna — and I wrote the song."

Released as a single in March 1968 Lady Madonna went to No 1 in Britain but stalled at Number 4 in America.