My blood test has shown 1:77 chance of baby having Down syndrome. I'm 39, weight is good, 12 week scan was good however, something must have shown in my bloods for the computer system used to generate this result. I've had Pgd/ivf for this baby because my daughter has cystic fibrosis and we wanted to avoid that this time. I know blood test measures hcg levels and I only just finished my ivf medication a week before the scan so I'm hoping this is why this has been flagged up as such high risk. Anyone else been through anything similar? Unfortunately, we would have to terminate if positive for downs because downs present a lot of lung and respiratory problems which poses a high risk for my daughter and we would never jeopardise her health and needs. Any advice will be greatly appreciated. Thanks.