Rosie and Ruby Formosa, who were born joined at the abdomen and shared part of the intestine, needed an emergency operation to separate them.
The identical twins, who celebrated their first birthday yesterday, underwent an operation at London’s Great Ormond Street Hospital the day after they were born.
Despite being told that survival chances were low, the sisters are now doing well and are “very happy and bubbly”, their mother said.
Mrs Angela Formosa, from Bexleyheath in south east London, said: “It was quite a tough journey, really. It’s quite emotional thinking back, thinking what we must have been going through at the time. It was really tough.”
The 32-year-old said it was “heartbreaking” when doctors told her that the girls had a small chance of survival, adding: “Every time we went for a scan, we were worrying whether there was still going to be a heartbeat.
“They weren’t making any plans to give birth to them. All of a sudden it was like ‘OK – we need to make a plan because they’re still here, they’re going to arrive, so now we need to make plans and where we will deliver and where we will go’.”
When asked if she thought the twins would make it to their first birthday she said: “No”, adding: “When I was pregnant I couldn’t see us getting this far. I was taking each day as it came.
Mrs Formosa also said her taxi driver husband Daniel, 37, “loves” being with the girls at home.