How do I turn off voicemail-to-text notifications?

How do I stop voicemails from appearing on my lock screen and in my notification center in the form of full text messages? I have already turned off live voicemail. I need the ability to see my missed calls without unlocking my phone. I am going through treatment and I get very personal medical voicemails that I do not want others to be able to read if someone picks up my phone.

I find it hard to believe that Apple would implement a feature that would put their entire customer bases' privacy in jeopardy without an option to opt-out, so I'm hoping to find the setting to turn this feature off and I'm hoping someone can help me out.

Thanks!