Reality stars Bill and Giuliana Rancic have experienced their share of highs and lows on their journey to parenthood, and unfortunately, tragedy has once again struck the strong couple.

"This whole season on Giuliana and Bill we've been trying to have another baby," shares Bill of the pair's popular E! reality show, which follows him, wife Giuliana and their son Duke.

"Unfortunately our surrogate Delphine, who we love very much, had a miscarriage," Bill reveals. "It's something that we didn't see coming. We were devastated."

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After Delphine successfully delivered Duke, now 21 months, in August of 2012, the couple were optimistic about another pregnancy, but remained cautious, refusing to announce the news until she was further along.

"She was about nine weeks pregnant. We were pretty close to getting into the safe zone," shares Bill. "We experienced a miscarriage years ago when we were trying with Giuliana, so we had been keeping the pregnancy news tight to the vest."

The 39-year-old E! News anchor had undergone multiple in-vitro treatments before turning to surrogacy following her diagnosis of breast cancer in 2011.

bill rancic

Bill and Giuliana with son Duke last summer

"Delphine is amazing. We hit the surrogate lottery when we met her," Bill says. "Obviously this was no fault of hers."

He adds, "It's a double sadness because we didn't want her to feel bad. And Giuliana was rather distraught at first, but she's tough. In times like this we rely on our faith. Once the tears went away we started to look towards the future."

The pair have no plans to give up on their dream of welcoming another child. "We're fighters. Hopefully we're going to have good news and Delphine will be on board one more time," Bill tells People magazine.

"We've had to battle it out and that's something that we're going to continue to do."