And the couple had plans to celebrate the happy news and renew their wedding vows in Costa Careyes, Mexico this year, an annual tradition for the couple.
However, due to the "swine flu" they've had to cancel their annual plans, at the same resort they got married.
Their four year wedding anniversary takes place May 10th, which happens to land on Mother's Day this year.
A source tells Life & Style, "Heidi was worried about border closings and her three small children. And of course, she's pregnant."
Instead, this year "Heidi and Seal have decided to renew their vows at home in LA," confirms their rep.
Better safe than sorry!
[Image via WENN.]