Hayes (35) is one of the favourites to make it through this weekend's competition.
He met his wife Erica when they were both working in pantomime in Dublin.
But the singer's wife is due to give birth very close to the final of the RTE show.
Richie said that he would love to attend the birth of their first child but that Erica understood that the talent show was a huge opportunity for him.
"If she goes, she goes. This is something we have no control over," he said.
"She's in the business; she knows what goes on.
"But I'm trying not to think that way. She's with me most of the time but I'm comfortable when I'm away because she stays with her mam and dad in Dublin.
"And she's had a fairly decent pregnancy, a tough few months at the beginning, but she's been fine recently, so that's been good," he added
Erica (33), from Clonshaugh, said that she knows that it is the nature of the industry.
"I'm just getting down to the normality and packing the bags for the labour ward. We don't know if it's a boy or a girl. I'm waiting until afterwards to paint the bedroom blue or pink," she said.
"The magnitude of The Voice had kind of taken over, but I'm not worried if I go into labour for the final.
"Look, whatever, we have no control over it, there is no point getting hyper or worried. But I could go tomorrow: you never know."
The couple, who have been together for more than eight years, started up the Richie Hayes Stage School in Waterford and Erica said it has gone from strength to strength.
"The stage school is our thing now; we have built it from the ground up," she said.
"I will be pretty much working up to the time I go into hospital. It is our business."
"I gave up my career for the school and I love it.
"I get such a sense of pride for the children seeing them come up through it."