Most parents heading into their fifties would be happy to see their children fly the nest.

But a 54-year-old mother-of-eight decided to embark on a programme of IVF treatment in the Czech Republic and has now returned home as a mother-of-ten.

Yesterday Karen Johnston told of her delight after she took her new twin babies Imogen and Asa home for the first time.

She said: “We’re all so happy the twins are back at home. It’s been a long time coming, but they are fighting fit and in very good health.”

Mrs Johnston kept a bedside vigil for the youngsters as they fought for their lives.

The twins were born 13 weeks premature at the John Radcliffe Hopsital, Oxford, on March 12 with Asa weighting 2lb 5oz and Imogen a mere 2lb.

They were eventually moved to theHorton Hospital, Banbury, and this weekend doctors decided the pair were well enough to return to the family home at Severn Close, Bicester.

Mrs Johnston, whose oldest son Daniel is 33, said: “Life is already very hectic. You are up every two hours during the night to look after them, something which doesn’t get easier no matter how many children you have.

“We prayed they would make it and they have.”

The twins were conceived in the Czech Republic using a donated egg and sperm from her husband Roger, 55, a former soldier who works at BMW.

At present, NHS Oxfordshire offers IVF treatment to women aged 30 to 35, who fit a specific criteria.

Although some private clinics in the UK will offer treatment to older women, travelling abroad increases the likelihood of getting treatment.

Mrs Johnston had her first four children, Daniel, Jemma, 28, Scott, 27, and Amy, 26, before suffering three miscarriages.

She then had Aiden, 17, Bethany, 14, and Joseph, 13.

Mrs Johnston said: “We have a large family and they are more like parents than siblings.

“We’re never short of babysitters and they all do their bit to help look after the twins.”

The couple decided to stop trying for children after Mrs Johnston suffered two further miscarriages.

But in 2006 Mrs Johnston discovered a 63-year-old British woman was having IVF treatment in Russia.

A year later she and her husband travelled to the Czech Republic and, following a course of treatment which cost £3,000, daughter Willow, now two, was born.

Last year they returned to the same clinic.

Mrs Johnston said: “We wanted a brother or sister for Willow.

“We were surprised when we heard I was expecting twins, and having two young babies is definitely proving a handful.

“But it’s all been worth it. I’m now just looking forward to a full night’s sleep.”

The birth had to be induced at the JR after Mrs Johnston suffered pre-eclampsia – hypertension caused by pregnancy – and needed an emergency blood transfusion.

Mrs Johnston added: “I’m now looking forward to being a full-time mum again.”