I've been meaning to review Jon Cohen's Coming to Term for a while now. I started reading it back last year when researching the best existing miscarriage-focused books, and only just last month did I get time to finish reading it cover to cover.

As a regular watcher of miscarriage headlines, I'd seen reviews of the book when it first released last year or so. Multiple sources said it was a great review of the known science behind miscarriages and that it provided hope for couples trying to conceive after multiple losses. So I went into reading Coming to Term with high expectations.

Overall the book was a great read. Cohen takes readers on a journey through most of the available research on miscarriage causes and incidence. You'll learn about most of the leading theories behind miscarriage causes and even the origins of some of those weird statistics everyone throws around, like the idea that 50 to 60 percent of all miscarriages are due to chromosomal anomalies. (I'd always wondered where that number came from.)

Coming to Term is a great walkthrough of reproductive biology. You'll understand why some doctors say one thing and others say another, and you'll finish the book having a better idea of what you're up against and maybe renewed hope that someday you'll see the light at the end of the tunnel. It's a great book and obviously well researched. I'd go so far as to say it's probably the best on the market for providing you with actual studies and information about the mechanism of miscarriages.

That said, I'm a nitpicker.

I do wish that Cohen had gone into more depth on progesterone. Progesterone, in suppositories, oral tablets, or shots, is probably the most commonly used miscarriage therapy. Yet it's controversial. Some doctors say it's utterly useless while others swear by it. Cohen discusses it a bit in Chapter 6, but I felt he could have explored the issue further. Many physicians prescribe progesterone but in vastly differing protocols. Some use pills, shots, oral tablets, etc. Some swear progesterone could only possibly be useful if taken starting in midcycle to support the uterine lining following implantation. Others, including the doctor I saw for my own losses, believe that it does not need to be supplemented until pregnancy is confirmed and a low progesterone level is noted. And recent studies regarding stress and miscarriages explore the possibility that stress reduces progesterone levels and that supplementing progesterone in early pregnancy could correct the problem. Given that progesterone supplementation is so common and still controversial, I think this is an issue that Cohen should consider expanding on should the book have a second edition.

I'd like to have seen coverage of other more experimental areas too. For example, Coming to Term does not mention the MTHFR gene, one potential miscarriage factor that I find highly intriguing. Of course this is a very new area of research, not definitively linked to miscarriage and without any real consensus on treatment if it is indeed linked. But it's something that physicians are testing for and some are treating, so I was hoping to see some discussion of it.

But my biggest problem with the book was more philosophical. I don't think it's fair to criticize Cohen for this, since he was purely the messenger, but I'll ramble about it here since I'm guessing I'm not alone here. What follows is my own opinion and interpretation of this area of medicine as a layperson.

Cohen presented the evidence as most mainstream physicians interpret it. Reading through the book I got the idea that the message was that many treatments are worthless because they have not yet been proven beyond a reasonable doubt. But I'm not sure that I agree in this case.

Studies are so frequently flawed. Some contradict others. It's hard to measure problems that aren't well understood. Many of the miscarriage studies I've read personally had such flaws. Let's return to the example of progesterone. One study (not discussed in the book, but which I read online and have now lost the link) that supposedly "disproved" the benefits of progesterone therapy for miscarriages had a sample size of only 78 random pregnant women that it split into two groups. But when you think about it, since it was a split sample, this means that they only treated 39 random pregnant women with progesterone. Probably only 5 or 6 of each group were going to miscarry anyway. And of those 5 or 6, maybe 2 or 3 had babies with chromosomal defects. Obviously progesterone isn't going to fix chromosomal defects. Then of the other 3 or 4, who knows what other factors were at play in those losses? It could be that only one woman in this sample would actually benefit from progesterone therapy, which wouldn't show up as being statistically significant. But because such studies fail to provide evidence in favor of the therapy does not mean that the therapy does not work when targeted properly.

I'd think you could only really study the efficiency of progesterone therapy if you prescreened your sample for women who had experienced multiple miscarriages with clinically documented low progesterone levels. Then supplement half of them with progesterone and see what the rate is like. Only then could you really know whether supplementing women with low progesterone levels would reduce the miscarriage rate. But I haven't seen a study that did this. (Although one may exist…I admit I haven't gone on a scavenger hunt to track one down.)

It seems like, in high stakes areas of medicine, you're often going to find a lot of treatments being used that are unproven. Miscarriage is one such high stakes area of medicine. So many treatments out there are being used, and some are probably beneficial while others aren't. When I was experiencing my losses, I was willing to try anything that might help and probably wouldn't hurt. Yes, maybe I would have carried a baby to term with no intervention eventually, but who's to say that taking progesterone supplements weren't what caused that to be my fourth pregnancy instead of my sixth or seventh? When the stakes are this high, then I'm just not sure if the treatment is worthless until years and years and dozens and dozens of studies have proven it efficient. Especially when the odds of it being harmful are so friggin' low.

I'll have to shut up on that angle for now since I have a habit of going off on a major tangent there. Other factors in my life beside miscarriages have led me to distrust the whole field of allopathic medicine anyway so maybe it's just me. And it really is an opinion rather than a universal truth that all people will agree on. But to tie this back to Cohen's book, I guess that would be my only objection. He didn't really take a strong stand one way or the other and remained, for the most part, impartial but I was grated a bit by the constant feeling that he was more in favor of trusting doctors and waiting for solid as gold evidence that treatments would work before trying them outside of actual experiments. I didn't like the foreword writer who called it something "to Cohen's credit" that he did not pass judgment on those who hold onto hope of experimental treatments. I do think it's to Cohen's credit that he remained more journalistic, but at the same time, I found it annoying that the way the writer phrased it came across as if she herself wanted to pass judgment on those who would try experimental treatments.

Oh well. Enough on that. In summary, this is a great intro to the research out there. It's a great starting point for learning more about the mechanisms of the miscarriage journey. Cohen has the advantage of having been there himself through his wife's multiple losses. It's a good read, and you're guaranteed to learn something even if you've been reading about miscarriages online for a while. Four out of five stars.