I had had Mamas and Papas Primo Viaggio SIP car seat found it quite upright and borrowed one of my friends chicco. But unfortunately I used Primo Viaggio one until 16 weeks. I have been searching about car seats on the internet since last week and read horrible things about car seats and babies oxygen saturation. I was already quite depressed and had lots of worries about my baby's health anyway. After reading all those stuff my mood has deteriorated and I started feeling guilty about not doing enough research before buying the car seat. I keep worrying about any possible harmful effect of a car seat (I should have used a carry cot or lying flat car seat). Please help me, I think I need some support and reassurance...