So, I tried looking this up online, but it seems to be such a personal issue that I couldn't make any sense out of what I was getting.

My question is this:

How long would a wizarding couple try to have a child before turning to magical means of conception?

And then, how long would it take to learn that none of the magical methods work, and turn to Muggle methods? This, I figure, is probably somewhat up to me, but I'm including it in case there is information on magical fertility methods out there.

And then, how long would they need to be trying Muggle methods before giving up and realizing that nothing was going to work? This is the main one that I couldn't really find.

Or is that a completely implausible idea as it is?

Basically, I'm trying to figure out my time line, and I'm having a couple break up over the lack of a child -- well, and other reasons, but that's the main catalyst. I have another couple also breaking up, and both couples would have gotten together around the same time. I'm worried that if couple A spends too much time staying together on the hope of having a child/family, that it will seem less plausible that couple B didn't break up sooner. I think I can arrange it, but I need to know if we're talking 5 years or 20 years . . .