Desperate to keep their marriage afloat,  Fergie told Josh WHAT?!

Desperate to get her marriage to Josh Duhamel back on track, Fergie has agreed to get pregnant - and she announced her change of heart in the middle of a Los Angeles Dodgers baseball game!

As The ENQUIRER previously reported, the Black Eyed Peas thrush and her hunky thesp hubby were fighting just six months into their marriage.

Josh, 36, was ready to start a family, while Fergie, 34, continued to party. But after some soul-searching, she agreed to chill and promised Josh they could start trying for a baby after her tour ends in the fall, say sources.

"Fergie turned to Josh right in the middle of the baseball game and told him she wanted a baby to make their lives complete," revealed a close friend.

"She says pregnancy will be a crash course in cleaning up her act."

While Fergie had always planned to have kids, she wanted to put it off for a while.

Josh is thrilled by her change of heart, said the friend. "He adores Fergie, and he can't wait for her to be pregnant."