DAN Medical Frequently Asked Questions

Pregnancy

I've just found out I'm pregnant. When do I have to stop diving?

Fitness and Diving Issue

Sifting through the published literature reveals why there is debate over the topic. Data are limited and, in many cases, apparently inconsistent. While this makes drawing conclusions more difficult, it should not be surprising.

Science is very rarely as clear-cut as might be desired. It is difficult to design an ethical experiment that tests only the variable of interest and controls for all others. It is the researcher’s job to design the best experiments possible, and it is the individual’s or advocate’s responsibility to examine the results and decide how to best respond to them.

The question of diving and pregnancy is a difficult one to study since the trend is for women to refrain from diving while pregnant2. Most physicians treat diving as they would any drug for which the evidence with respect to pregnancy is incomplete: If there is not a good reason to take it, avoid it.

Anyone who inadvertently dives while pregnant, however, may take solace in the anecdotal evidence from women reporting repeated diving during pregnancy without complication. There is certainly insufficient evidence to warrant termination of a pregnancy. Moreover, if emergency hyperbaric oxygen is required during pregnancy, for example to treat carbon monoxide poisoning, the evidence suggests that the risk to the fetus with treatment is lower than without.

The overall picture of the literature indicates that, while the effect may be small, diving during pregnancy does increase the risk to the fetus, and the consequences could be devastating to all involved. Appreciating these essential factors, the prudent course is to avoid diving while pregnant. While it is possible that some diving could be completed without impact, the absolute risk of any given exposure cannot be determined from the available data. Given the ethical challenges of research on diving during pregnancy and the fact that diving represents a completely avoidable risk for most women, it is unlikely that studies will be conducted to establish the absolute risk in the foreseeable future.

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