The mother of a premature baby saved by a transfusion is urging people to donate blood, saying "just do it and see if you can save somebody's life". Sian Waugh's son Conan weighed less than 800 grams when he arrived 15 weeks early. Her pregnancy was progressing normally until 25 weeks when she was rushed into hospital and gave birth. At two days old, Conan needed a blood transfusion after suffering a haemorrhage in his tiny lungs. A second transfusion was carried out in the days that followed. Ms Waugh, from Midlothian, said it completely transformed Conan, who is now a healthy 18-month-old. She said: "It was like a tonic, he just had a teaspoon as that's all he needed in his body. It was like a completely different baby. He went from strength to strength after that." Conan had a long road to recovery but was finally allowed home after 112 days in hospital. He is now a "normal happy baby", thanks to the blood of an unknown donor. Ms Waugh said people are often shocked when she tells them how ill her son once was. She said: "Everyone just looks at me and doesn't believe me because he just looks like a normal 18-month-old." For the 36-year-old, the hour it took for a stranger to donate blood has given Conan a whole new chance at life. "If that person came in the door now and said 'I was the one who gave that blood to Conan', I would hug them and wouldn't stop hugging them. The reality is that transfusion saved his life," she said. The Scottish National Blood Transfusion service requires 550 blood donations every day to meet the needs of patients in Scotland and just three teaspoons of blood can save the life of a premature baby. Each of the eight blood groups must be maintained at five to seven days' supply and there is a particular demand for O negative and O positive donations. Blood stock levels can be checked at the Scotblood website. The donation service is calling for people to give blood at a time of year that traditionally sees donations drop by up to 20%. Lynne Willdigg, head of donor services for the west of Scotland, said this was due to the demands of the festive period. She said: "People's lives are very busy. We forget to take time out - we're all so busy rushing about, we've done our Christmas shopping, we're now preparing already for New Year. "Taking that time out to go and make a donation is important. It's something that will make a difference." Ms Willdigg also highlighted the next few weeks of the year as the perfect time for change and hopes that signing up to donate blood could be a popular new year's resolution. She said: "We waste so much time in our life doing things which are unimportant but the best gift that Sian and Conan have received was the blood transfusion which someone took the time to donate.