One of the things I love about NFP is the communication that you get out of it. It's a bit awkward at first, but you do develop a way of talking about it that's comfortable for you both. ...I'll get out my chart and show him where I'm at... giving details about how likely I think getting pregnant is along with comparing my signs to the objective rules, sometimes guessing as to when I'm likely to be infertile again. Then, it's not a yes or no answer, but a mutual decision whether to accept that probability of conceiving a child together right now.
(bolding mine) I think this is important. I won't give DH the gory details, but I can tell him I've noticed fertile cm, remind him what that means, and leave it at that. He looks at my chart, sees temp shifts or whatnot. It does help me feel like he is more involved, much more so than when I was on the mini-pill. Rather than a totally abstract risk (i.e. what if the pill fails?), I can give him some empirical info to make a decision. We decide together, and JMJ is right - it is helpful to keep a dialogue about fertility/preventing/etc.