Running a marathon pregnant: Is it safe??

(This is probably not what you expected to read...)

Amber Miller's completion of the Chicago Marathon 38 weeks and 5 days pregnant has changed the world of women's running. Now runners and non runners alike know it is possible for a pregnant woman to run a marathon.

Was her doctor right to let her do it? Well, there has thus far been no evidence that running a marathon pregnant is dangerous for the mother or baby. The evidence is only anecdotal, though. There is however a lot of evidence that "moderate" running is both safe and healthy (and may even produce calmer, healthier, more coordinated and smarter kids... but Klapp's studies were small).

I ran 6 marathons during my most recent pregnancy. Almost every reader here probably thinks I am a biased proponent of running marathons and am going to try to convince you that there are no dangers. But that is actually not the case.

The fact that Amber's marathon appeared to induce her labor brings up a lot of concerns. Had she run the marathon at, say, 34 weeks, would it also have induced labor? Is there enough anecdotal evidence to say no?

She was already far enough along in her pregnancy that the baby could be born without any of the risks of prematurity. But what if she hadn't been so far along?

The last marathon I ran while pregnant was at 30 weeks and was the Copenhagen Marathon. I ran it in 4:54, which didn't seem that fast at the time, but in retrospect was probably too fast and more than my body could tolerate. I felt fine the night after, but the following week, I felt unwell, extremely fatigued and merely walking was enough to induce Braxton Hicks. Two weeks after, I was better again. But WAS I close to inducing premature labor? Was my water close to breaking? I do not know. There is simply not enough evidence.

The 5 pregnant marathons I had run prior to this did not take nearly the same toll on me. Perhaps not unimportantly, they were all run in very small races.

What would my advice as a physician be to women who want to run a marathon pregnant? Well, if they feel they are up to it, I would say it is safe, if their pregnancy was uncomplicated and they were healthy, experienced runners. HOWEVER, I would strongly encourage women who are beyond 26 or 27 weeks to avoid large city marathons and simply run the marathon in a small group or with friends. I find that in large city marathons people push themselves beyond what may be healthy for their body, simply due to the excitement and cheering crowds. If a woman gets too caught up in this, she may start ignoring warning signals that might otherwise stop her from continuing.

It is only a theoretical risk, but until there is more evidence, that would be my recommendation.

But where is that evidence going to come from? Well, I got an idea today. I am going to start a database of pregnant marathons. If you have run a pregnant marathon (or ultramarathon), you are more than welcome to contribute. You send me an email at sealegsgirlblog@gmail.com and I send you a rather extensive questionnaire about the race/s you ran, your time, your previous running experience, how far along you were, how you felt short-term afterwards and of course the pregnancy outcome (also be prepared to answer questions about your medical and obstetrical history). It is biased, sloppy reserach. But it is likely the only kind of research one can do about pregnant marathoning and it is better than nothing. The database will be found at a website, which I don't have a link to yet. Here women who are interested in running a marathon or half marathon pregnant can see what other womens' experiences have been and then contribute their own. Ultimately, women will get connected to it, not through this blog, but through the new website.

As of now, I'm open to any sort of suggestions you have as this project will take a while to implement if it is going to be a good resource.