Pregnancy is an incredible, life-changing experience. It also carries with it a long list of do’s and don’ts. Many of these are common knowledge: we all know that smoking and drinking are ill-advised during pregnancy, for example – but where does diving fit in? Research on the subject is limited, due in large part to the fact that it is unethical to conduct potentially dangerous experiments on expectant mothers. In this article, we take a look at a few of the theoretical risks for Mom and baby, and the evidence that exists to support them.
The Potential Risk to the Baby
Scientists and medical professionals have two main concerns about the effects of scuba diving on an unborn fetus. The first is connected to a fetus’ exposure to hyperbaric oxygen or oxygen that has been concentrated by pressure. It is thought that this kind of exposure has the potential to alter the signals that tell fetal tissues when and how to develop, potentially resulting in a change in how those signals are interpreted. Depending on the stage at which the exposure occurs, this could lead to a range of different issues – including abnormal development of the skull, heart or limbs; limb weakness; premature delivery or even miscarriage.
For this reason, the effects of hyperbaric oxygen exposure would likely be most severe in the first trimester, when the most important developmental changes occur.
The second concern is connected with decompression illness (DCI), which has the potential to affect the fetus throughout pregnancy but is likely to be most dangerous during the third trimester. Foetuses are thought to be at risk of developing DCI even if the mother remains within no-decompression limits. Sometimes, “silent bubbles” form in the bloodstream during a dive. These are safely filtered out by the mother’s lungs; however, fetal blood circulation bypasses the lungs, with gas exchange occurring via the placenta instead. The bubbles remain in the fetus’ system, therefore…