- Rob and Jennie Macphee began IVF in 2008, the day after getting married
- Over two years they suffered six failed attempts and one miscarriage
- Later found Mrs Macphee's strong immune system was attacking embryos
- She had injections of soy and egg products and became pregnant
- Twins Dylan and Niamh were born in 2011 followed by 10-week-old Orla
A mother desperate to start a family endured six failed IVF attempts - only to discover her over-active immune system was attacking her babies.
Jennie Macphee and her husband Rob, from Stamford, Lincolnshire, began trying for a baby immediately after they got married in 2008.
The couple had been warned that despite the fact they were still in their 20s, they may experience problems conceiving after Mr Macphee, 35, had surgery as a teenager.
They saved for IVF, but faced the heartache of six failed attempts and one miscarriage over the course of two years - at a total cost of £21,000.
After researching alternative types of IVF treatment, the couple later discovered Mrs Macphee's strong immune system had been rejecting the embryos, preventing them from implanting.
The nurse, who is now 34, began a course of intralipid therapy, where she was injected with soya and egg products to tackle 'killer cells' in her immune system.
Months later, the couple were delighted to discover they were expecting.
Twins Dylan and Niamh, now four, were born in 2011.
And they were followed by 10-week-old Orla, who was conceived using the same frozen embryos as her older siblings.
Mrs Macphee said: 'For years we knew that we may have trouble conceiving because Rob had an operation when he was younger, but we never imagined that I would be the reason why we were struggling to get pregnant.
'We had our first round of IVF on the NHS the day after our wedding day.
'We were hopeful because we were still in our twenties at the time, but it turned out to be unsuccessful.
'We saved some money for our next round and moved to a different clinic and we later had another four rounds. I also had a very early miscarriage.'
She said experts told the couple they were producing good embryos, but warned they wouldn't implant.
'It was a very difficult time for us,' the now mother-of-three, said. 'We were nearing our 30s and our friends began having children.
'It was difficult to watch at times but it made us more determined.'
After two years of difficulties, the pair visited an IVF specialist who told Mrs Macphee her chances of conceiving were less than eight per cent because her immune system was so strong it was destroying the embryos before they had chance to attach.
'I had never considered that my immune system was preventing me from having a successful pregnancy,' she said.
'I had never heard of it before and when the consultant told me I had an eight per cent chance of having a live pregnancy I just thought "oh my God".
'I couldn't believe it.'
The couple gathered enough money to fund an alternative course of treatment that would attempt to weaken Mrs Macphee's immune system.
She began having intravenous doses of egg and soya products every fortnight for three months, and in September 2010 the couple discovered she was pregnant.
'We took the pregnancy test before we attended a friend's wedding and we were delighted,' she said.
'We didn't dare feel too excited because we had been there before.
'The first scan was absolutely mad. My husband and I were looking at each other in complete disbelief.
'When we were told we were having twins everything felt perfect.
'We had always wanted more than one child and we had been trying for so long.
'When the twins were born we brought them home in their car seats and put them together in the living room. It was a lovely feeling and we were so ready for them.
'We asked the clinic to keep some of our embryos in case we wanted to try again but we'd convinced ourselves it wouldn't happen again.
'At the end of last year I'd become broody again so we decided to go back and start the treatment.'
The couple said they couldn't believe it when the treatment worked first time.
Orla was born in May, and the twins are preparing to start school in September.
Mrs Macphee said: 'Our family is complete now.'
Miss Maha Ragunath, medical director at CARE Fertility in Nottingham, said: 'To endure multiple failed implantations or miscarriage is devastating and our experience has shown that some women may benefit from specific blood tests to check for abnormalities in their immune system.
'We are looking for an increase in natural killer cells which are implicated in failure of embryo implantation and miscarriage.
'We would typically offer these tests to women over 35 who have had two miscarriages or two failed IVF cycles, perhaps previous immune problems such as rheumatoid arthritis or lupus.
'If a problem is identified, treatment is quite straightforward. In Jennie's case, we prescribed intralipid therapy which is a solution based on egg and soya products as part of her IVF cycle.
'Given in drip form by a trained nurse, the infusion is inexpensive, well tolerated and is shown to calm down an over-active immune system, allowing an embryo to implant in the womb. Eating more eggs or soya doesn't work.
'If a pregnancy test is positive, intralipid can be given every four weeks until the twelfth week of pregnancy to allow normal development and prevent miscarriage.
'There are many causes of treatment failure in IVF and miscarriage and each patient needs individual assessment, but if an immune issue is found, we do have treatment available.'