Antony Probets carried on sleeping as his girlfriend Gemma McSheffrey went on to have the couple's baby girl all on her own.
Gemma, 20, said: "I was screaming for Antony all the time but he was fast asleep so I did it all on my own.
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Sleepy head: New dad Antony Probets snoozed as girlfriend Gemma McSheffrey gave birth to their daughter Paige
"Then I walked into the bedroom with the baby in my arms."
She added: "Antony is a very heavy sleeper. I can never wake him and he's always the last one up."
Antony, 19, a chef in Elland, West Yorkshire, where the couple live, said: "I thought I was dreaming at first so that's why I didn't wake up.
"When I realised it was real I was so shocked."
He added: "I'm sad because I wanted to be there for the birth but I am so proud of Gemma."
The couple had gone to Calderdale Royal Hospital after Gemma, started having contractions.
But staff sent them away because the first-time mum was still only in the early stages.
Gemma said: "When we got home my contractions started getting worse.
"The next thing I knew my waters had broken. I had a really big urge to push so I did and half her head was out."
Two more pushes and less than 10 minutes later little Paige Elizabeth Probets, weighing 7lb 3oz, popped out at 6.30am.
Gemma, who works on a fruit and vegetable stall, had not been to ante-natal classes.
She said: "I was absolutely terrified because I didn't have a clue what to do but I didn't want the baby to become distressed.
"Friends who have had babies said it really hurt but I didn't have time to think about the pain."
Gemma wrapped the baby in her dressing gown and headed back to the bedroom where her boyfriend was sleeping.
"I said 'Antony you need to get up now' but he didn't really function for about five minutes. It was actually Paige that woke him up crying."
The new dad got to cut the cord before they headed to hospital with the ambulance crew.
The couple who have been together for 11 months, brought baby Paige home on Friday.