The not knowing is what's getting to me the most.
A small part of me feels that I wish I could stop trying to get pregnant now. I could begin mourning the loss of what I thought my life would be, the loss of a child of my own. I could resign myself to living childless and begin wholly focusing on other things once again.
But because I am 38 and we are "unexplained," simply ceasing TTC efforts doesn't necessarily mean that we would never get pregnant. At this stage, I would consider it more likely than not that we would not conceive on our own. . . . but no one can give an accurate answer to that question. Our RE wouldn't even give us an opinion on what the odds of our succeeding with Clomid + IUI would be, so I doubt he would even hazard a guess about what our odds of conceiving naturally are; there are just too many variables, too many unknowns.
Everyone has an anecdote of someone they know who conceived after doctors gave them a less than 1% chance of conceiving without ART. I actually have two friends in real life who had this experience, not to mention people I have heard of or met online. A message group friend of mine just gave birth to her first child at the age of 44, the result of a pregnancy conceived without the use of ART; if asked, I think most doctors would say that the odds of something like that happening are quite low. I have friends who conceived on a break cycle after their second failed IVF. . . . and then conceived again naturally (& unexpectedly) when their "miracle baby" was only four months old.
The fact of the matter is that there is a lot more about the process of conception, implantation, and pregnancy that the medical community DOESN'T know than what they do know. "Unexplained infertility" is really a misnomer because it implies that everything about each partner is normal and yet they cannot conceive. The true situation in most cases is more likely that something IS wrong; it just happens to be something for which doctors cannot test.
When we first had our basic testing done by our RE, I remember having some friends (who'd never experienced problems TTC themselves) who said "oh, you must be relieved to learn that all your tests were normal." Far from it. Instead, my reaction was more like "well then, what the fuck?!" (Pardon my French.)
Our RE has told us that he believes that the most likely explanation for our failure to conceive thus far is poor egg quality related to my age. However, as my sister astutely pointed out, he honestly can't know that that is the problem. It's more likely that he has simply drawn that conclusion because it is the most obvious explanation. After all, women far younger than I are diagnosed with "unexplained" infertility all the time. (I suppose their REs have to present a different hypothesis for the cause of their problems.)
I don't like the unknown. I don't fear it, but I don't like it. My husband and I are both planners. As it stands right now, it's difficult for us to plan things more than a few weeks in the future because we don't know whether or when we will be parents.
A part of me thinks that we should just stop "trying" and go on with our lives. Go ahead and plan a life that does not include children and just be pleasantly surprised if we get pregnant unexpectedly. But I don't think that MM is ready to do that, and I'm not 100% convinced that it would be the right decision for me either. It still wouldn't totally solve the uncertainty problem.
Ah, how I envy those whose lives go according to their plans! Yeah, there are people like that; I know a few of them. People who get pregnant within the first 1-2 months off birth control, who can plan their pregnancies and deliveries at the times of year most convenient for them. People who get to decide how many children they will have and how far apart they will space them.