My cousin is pregnant now and her son before this also had that. Her son is 5 . She's 7 months along. Its not uncommon and Dr knows how to handle it. Just means your bundle will be very looked after.
My best friend had that. All it means is that your baby isn't getting all the nutrients that a 3 vessel cord pregnancy gets. Your doctor will probably up your calorie intake. And you may get weekly ultrasounds towards the end. My friends baby is 4 months now and as happy and healthy as can be.