Like many of you, I am addicted to reading material in the domain of infertility. And like many of you with online access to journals via a university, I head right for the primary source material. I loves me some Fertility & Sterility, the Official Journal of the American Society for Reproductive Medicine! I get the alerts when a new issue is coming out and everything, so I can make sure to read papers such as Estrogen and progesterone receptors in smooth muscle component of deep infiltrating endometriosis. (Um, yeah, not so much on that one.) But despite my desire to avoid unreliable information, and even with all my training as a social scientist, I find that I am still susceptible to a basic flaw in human cognition: we tend to look for evidence that will confirm whatever it is we want to believe. Psychologists have labeled this the confirmation bias, and suggest it's part of a family of principles in human thinking. These principles are adaptive in the sense that they allow us to reason quickly, and don't lead us to be eaten by tigers all that often. I mean, if you encounter a tiger, it's better to believe that all tigers will eat you than to believe that every tiger you've encountered thus far will eat you, but perhaps this next one won't, and you should really test your hypothesis in a way that might allow you to falsify it. So while these principles may not lead to accurate reasoning, um, humans don't reason accurately. And yet we do pretty well for ourselves.
So lately the confirmation bias has manifested itself in a somewhat...selective...approach to reading on my upcoming surgery. Basically, I'm looking for things that will convince me my fertility will be radically improved. That I'll instantly have a hundred fat, happy babies. There are plenty of papers with small numbers of patients that present encouraging figures (e.g., in the year following the surgery, 40-70% of women conceive, with age being the major factor that improves your prognosis). Buuuut...there almost no studies where the entire participant population consists of infertile women or women with recurrent loss. So there's no causal link between the surgery and improved fertility. (Because women who conceive after the surgery might have conceived anyway--they weren't infertile.) In addition, there are several review papers on the surgery that present a more discouraging picture. These are papers that summarize and evaluate lots of other papers, rather than presenting new research. And they are much more cautious, pointing out that many of the encouraging studies are, to use the scientific term, crap. Anways, guess which ones I like to read? I repeatedly find myself looking at abstracts that end with an encouraging conclusion--those papers I download and read. But the abstracts that end with a discouraging conclusion--those I pass by. 'Cause I don't want to learn. I don't want to know the truth. I want data that will confirm what I want to believe.
Fortunately, in my case it doesn't matter whether the surgery helps or not: I can't have IVF without it.
And at least today I found a paper with COLOR PHOTOS of the procedure! Really cool! It shows the different sutures used for different layers of the uterus and everything! Perfect lunchtime reading.