She went into labour three weeks early and gave birth to her first child, daughter Esmay, with the help of a make-up mirror in her bathroom.
"My colleagues had joked that I would end up delivering my own baby but I never thought it would actually happen," says Claire, 28, from Hawkhurst, Kent.
Leaving work at Croydon University Hospital l at 10pm, a week before her maternity leave was due to start, she endured a restless night before, at around 5am, she woke husband Tim as she began to have contractions.
"I had a bit of backache but put that down to the long shift," she says. "At about 5am I began to realise I was having contractions but as it was my first time I knew it would probably take a long time so I told Tim I was probably looking at giving birth maybe on Tuesday so I'd wait and see.
"I ran myself a bath and suddenly the contractions can on fast. I was laughing because it was so unexpected. The contractions just kept coming and coming."
Paramedics were called but Esmay Clarke-Wood was born before they arrived with her mother using a make-up mirror to monitor her own childbirth. Esmay was a healthy 6lb 12oz.
Claire, who's attended numerous home births, says: "Afterwards it was just like I was at work, I was clearing away the towels and putting on a cup of tea - Tim was just trying to get me to settle down."