According to The Sun, the Spurs footballer teamed up with Clancy's mum Karen to arrange the party, which took place at the couple's home in Surrey.
A source said that Abbey had "no idea" what was going on when Karen took her out of the house for a couple of hours, giving Crouch time to sneak her friends in.
"She had thought Peter was spending the day relaxing and was amazed when she got back and everyone was there," the source said.
Crouch and Abbey announced that they were having a baby back in September. The pregnant model is expected to give birth within the next few days.