What age is too young for ivf?

My parter and I are discussing ivf, after several miscarriages were now discussing going down the ivf route. My fiancée has cystic fibrosis (I don't carry the gene so we've been told by doctors that 100% our baby would not have cf) after a miscarriage last week we're beginning to feel like ivf is our only option, only problem is im only 23 and feel too young to be having ivf, we've been together 9 years and are desperate for a baby. I just don't know if I feel comfortable with ivf yet?