Is it always a risk?

The reason that repeat c-sections are a risk is the scar tissue. If you've had 4 previous c-sections than yes, you're at more risk than a woman going through her first.

Is your pregnancy high risk? There's really no way to answer that. You are unique, your case isn't the same as someone else. Your body reacts differently than anyone else's, you heal differently, you scar differently.

Your doctor will be able to better assess what risks there are.