And Marc even saved his son`s life when he was born with the umbilical cord wrapped around his neck.
Sasha, an administrator, who was on the contraceptive pill, had no idea she was pregnant - throughout nine months she had no bump, felt no kicks and even continued to have periods.
Yet baby Theo, who is now two months old, was a bouncing 7lb 6oz when he made his entirely unexpected entrance in the world, forcing his father into the terrifying role of midwife when they didn`t make it to the hospital in time.
Stunned Marc then announced the surprise birth to friends and family on Facebook writing: `Well what can I say… 24 hours ago we had no idea and at 16.45 yesterday Sasha gave birth and I delivered (don`t ask!) our beautiful son at home.
`This is a massive surprise to us both as we didn`t even know she was pregnant until yesterday.`
Sasha said: `Even now I look back and wonder how I didn`t know I was pregnant. But I took my pill like clockwork. Until it happened to me, I never imagined any woman could have a baby and not realise she was pregnant.`
In fact, the first indication came one evening in March when Sasha began to get stomach cramps.
She said: `I took some painkillers and went to bed and even managed to go to work the next day.
`But when I got home the pain was suddenly worse so I made an appointment with my GP for 10am next day.
`After an agonising night I explained my symptoms and I was really worried when the doctor looked surprised as she examined my tummy.
`However I was shocked when she said she was referring me to the maternity unit.`
She immediately rang Marc. `We`d spoken about having a family but that was years off,` she said, `so I had no idea how he`d take it.`
Marc said: `I simply couldn`t believe it at first. But then relieved Sasha didn`t have some terrible illness, I think I said something like "this is crazy" and then I said something like "that`s great news…" But then I had no idea Sasha was actually nine months gone.`
Marc met Sasha at hospital, where doctors estimated she was approximately 28 to 32 weeks pregnant.
Adds Marc: `I asked Sasha how we possibly couldn`t have known, but medical staff said that no contraception is 100 per cent foolproof and although rare, surprise babies can happen.`
The couple were sent home after the pains subsided.
But within a few hours the pains returned with a vengeance. As Sasha cried out in agony, Marc dialled 999.
Sasha said: `I`d had a bath to help soothe the pains but as I lay on the bathroom floor I felt the urge to push.`
Still on the phone to the paramedics, Marc rushed to find clean towels and reassured Sasha help was on its way.
But within 15 minutes baby Theo arrived - only he wasn`t crying.
Sasha says: `It was a frightening moment as Marc and I realised the cord was round the baby`s neck. Luckily Marc followed all the instructions from the paramedic on the phone and managed to free Theo. Hearing him finally cry was wonderful.`
Dazed Marc, who was still on the phone to the paramedic, wrapped baby Theo in a towel and handed him to Sasha.
She said: `I was so relieved I sobbed. When I handed him back to Marc and saw him proudly hold him, I was overcome again with emotion. It was clear despite the shock, Marc was overjoyed to be a dad.`
There was a bang on the door - the paramedics and Mark`s mum Shirley had arrived.
`Marc`s mum said congratulations. She was in tears of joy and she was as stunned to suddenly be a grandma as we were to be parents.`
Baby Theo was checked and found to be perfectly healthy. Doctors even estimated that he was actually four days overdue.
The couple named their new baby Theo - which means gift of God in Greek - and they are slowly adapting to sleepless nights and being parents.
`But even though we were totally unprepared, we are so happy to have Theo,` says Sasha, `we both still look back and can`t believe we didn`t know we were having a baby.
`But he is absolutely adorable and now we can`t imagine life without him.`
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