Scuba diving in second trimester

[doctormike]

I had a very similar discussion (over PM) recently with someone with a history of a perilymph fistula who wanted some sort of blessing from an ENT doc that it would be OK for him to dive. A similar situation to this one, but with much lower stakes, of course.

He was convinced that since we didn't have good evidence that diving after PLF caused injury that we (i.e. the docs that he had consulted) were just being obstinate and overly cautious in telling him not to dive.

He was making the same error that it sounds like the OP is considering. I told him the same thing that I would tell her: "The absence of evidence is not evidence of absence".

 

[Donnah]

Just don't do it. It's way too risky for the baby. Too much can go wrong. And if you do, for the rest of the child's life, whenever anything happens, you will always wonder if your diving did something to cause that.

 

[Rich Keller]

There has been no research in humans for obvious reasons. I know there has been studies with rats and sheep. Pregnant sheep are the closest match to humans as far as this type of research is concerned. One effect they found and cannot explain is that the fetus seems to be far more susceptible to the bends then the mother, causing it severe problems even though the mother is diving well within safe limits and unaffected. Other problems would be premature birth, low birth weight and larger then normal percentage of birth defects. I am assuming this research was done by the NEDU but I could not find anything on line about that. Your best course of action would be to contact the NEDU for more information, even if they did not do the studies they will be able to give you a far more detailed answer then I can.

 

[danvolker]

Just snorkel if you are going no matter what.
If you are good at freediving, keep your drops under a minute and don't push your CO2 buildup.
If the reefs you visit are 30 feet deep or shallower, you really don't need scuba tanks.

 

[Griffo]

The GBR (at least the parts i've seen) are simply not worth risking getting a cold to dive, let alone the life of an unborn child. The Yongala is special enough to risk a cold for, but seeing as it's a high-current dive it's even higher risk for DCS symtoms so would be even crazier to do pregnant.

 

[welsh98]

What does DAN say ?

DAN replied with the following;

"Thank you for your e-mail and interest in DAN. We agree with the information you have cited and yes shallower dives do reduce the risk of decompression sickness (DCS). They also reduce the potential nitrogen tissue load. As you have found in your research how the excess nitrogen may or may not affect the fetus is inconclusive. You need to accept the fact that even though shallow dives general represent a low risk for DCS the risk of a possible arterial gas embolism (AGE) is still present. In the albeit unlikely event of an AGE definitive care is to be treated in the chamber. It has been established that hyperbaric oxygen therapy is detrimental to the fetus. The actual risk of an AGE can be debated ad infinitum but regardless the risk has to be considered. The consensus opine among dive knowledgeable obstetricians that any diving involving scuba or any other compressed gas source at depth should be suspended during pregnancy. The risks cannot easily be quantified and the safety of the both the mother and fetus are the priority. Pregnancy already has several recommendations that curtail certain choices such as tobacco use, alcohol consumption or sports activities that could cause trauma. Diving should be thought of in the same way. We wish you a happy and health pregnancy and you can look forward to returning to diving. If we can be any further assistance do not hesitate to contact DAN."

---------- Post added January 29th, 2014 at 07:13 AM ----------

No one knows how fetal tissue, especially developing fetal neural and eye tissue, responds to things like microbubbles and elevated PPO2. No one knows what the long term effects of those physiological changes would be to a developing fetus. Just because people have dived while pregnant and have had children without obvious injury doesn't prove anything.

On the other hand, the OP didn't ask if she should dive, her question was "how many of you have dived pregnant?" My question would be "why would that matter?"

It matters purely out of interest. I wouldn't accept anecdotal stories as evidence however I am curious to know if there are more pregnant women secretly diving than previously thought.

---------- Post added January 29th, 2014 at 07:15 AM ----------

Check the following thread: http://www.scubaboard.com/forums/womens-perspectives/186531-effects-diving-pregnancy.html

Also check out:

DAN | News
https://www.diversalertnetwork.org/medical/articles/download/OB & Diving.pdf
http://ddrc.info/research/docs/mstld_jog_2006.pdf
http://dspace.rubicon-foundation.or.../123456789/6271/SPUMS_V26N1_10.pdf?sequence=1
http://europepmc.org/articles/PMC1670333/pdf/bmj00132-0046.pdf

 

[welsh98]

Seriously? How many dive centres, exactly, are telling you that?


Sent from my iPad using Tapatalk HD

Whilst I was waiting for DAN to reply to me, I called a couple of Victorian Scuba centers, as well as the Melbourne scuba academy, a place up Qlnd and the place I got my Padi license in FIJI.

---------- Post added January 29th, 2014 at 07:48 AM ----------

There has been no research in humans for obvious reasons. I know there has been studies with rats and sheep. Pregnant sheep are the closest match to humans as far as this type of research is concerned. One effect they found and cannot explain is that the fetus seems to be far more susceptible to the bends then the mother, causing it severe problems even though the mother is diving well within safe limits and unaffected. Other problems would be premature birth, low birth weight and larger then normal percentage of birth defects. I am assuming this research was done by the NEDU but I could not find anything on line about that. Your best course of action would be to contact the NEDU for more information, even if they did not do the studies they will be able to give you a far more detailed answer then I can.

They used sheep because a sheep's placenta was the 'closest' match to a humans. The study was also done 'only' on deep dives. Infact most of the studies were on deep dives or included deep dives.
That study has also been rebutted.

As far as I can deduce, the risks with diving pregnant are lowered with a) shallow dives & b) anytime after the 1st trimester (this is due to the vital organs develop in the 1st trimester).
If I could speak to a Neonatologist about the exact filtration adequacy of the placenta, I would consider a shallow dive.

I'm tired of all the lies and twisted truths about 'do's n don'ts in pregnancy' so I tend to not take anything at face value, hence the in depth research.

But with all said and done....... I think you guys are right with what I hear about the GBR being trashed and not that great a dive?!

 

[jamesdiving]

The GBR (at least the parts i've seen) are simply not worth risking getting a cold to dive, let alone the life of an unborn child. The Yongala is special enough to risk a cold for, but seeing as it's a high-current dive it's even higher risk for DCS symtoms so would be even crazier to do pregnant.

Would have to agree. I dived the GBR 13 years ago and the Yongala was, at the time, the best dive I'd ever done. 13 years on, based on a lot more diving in a lot better places, I wonder if it would still compare. The rest of the GBR was average back then when compared to the Florida Keys and the Similan Islands. I don't imagine the GBR has improved much in that period - and the description "not worth catching a cold" seems pretty apt.

No original insights on diving while pregnant, but for what it's worth the risk/reward ratio seems pretty skewed to me - a couple of half-decent dives v life time of worry/guilt/regret. I hear the analogy with flying, but as another poster pointed out, the physiological impacts of the two seem, at least to my non-scientist mind, of significantly different magnitudes.

 

[doctormike]

As far as I can deduce, the risks with diving pregnant are lowered with a) shallow dives & b) anytime after the 1st trimester (this is due to the vital organs develop in the 1st trimester).
If I could speak to a Neonatologist about the exact filtration adequacy of the placenta, I would consider a shallow dive.

I'm tired of all the lies and twisted truths about 'do's n don'ts in pregnancy' so I tend to not take anything at face value, hence the in depth research.

OK, I’m gonna take one more shot at this, and give you the benefit of the doubt that you are not trolling us.


Your adversarial tone towards the medical advice that you have received suggests to me that you want to do something that pretty much everyone with any qualifications tells you not to do, so you are just going to keep doing “research” until you have satisfied yourself that what you are doing is safe. There are lots of threads here that are similar (e.g. “I’m gonna do a bounce dive on air to 200 feet on an aluminum 80&#8221, the difference being that in those threads only the OP can get hurt, so we eventually drop the discussion and defer to Darwin.


Once again, the absence of evidence is not the evidence of absence. What you call “lies and twisted truths” are people with good intentions making the best guess about a clinical scenario where there can never be valid scientific data. The only way to prove the hypothesis that you are making would be to take a large number of women in the second trimester, randomize them into a group doing shallow diving and a group doing no diving, and then to do long term neurological, audiological, ophthalmological, behavioral and developmental studies on the children born of this group over the next decade or so. That’s not going to happen.


If you think that a neonatologist would be able to give you a better answer because they know about the placenta, you are demonstrating a significant lack of understanding about how medical research works and the role of conjecture based on no data.


Finally, when you say that the risks are lowered with shallow, second trimester dives, that implies to me that you have some data about the numerical risks of that vs. the risks of deeper or first trimester dives. I don’t believe that any such data exists. And even if it did, that doesn’t support your hypothesis. Yes, it is much safer to text while driving than to drive blindfolded and drunk. But don’t text while diving, OK?


I hope that you don’t think that I am being rude, condescending, or patronizing. I do realize that there are serious cultural and societal issues related to externally imposed limits on a pregnant woman’s activities, especially those with no basis in fact (like the old recommendation to avoid flying). I just don’t think that this is one of those cases, and I hope that you understand that I am just trying to help.


BTW, congratulations!

 

[ferris213]

I'm tired of all the lies and twisted truths about 'do's n don'ts in pregnancy' so I tend to not take anything at face value, hence the in depth research.

I'm guessing your research has shown no proof that it is safe?

We investigated diving while my wife was pregnant, our doctor said there was no human tests, so why risk it. As others have said, if my wife had chosen to dive, and something went wrong with the pregnancy or baby's development I don't think we could live with ourselves. It's just not worth the risk.

Your profile says you in Australia, so accessing the reef shouldn't be a once in a life time type opportunity. Good luck with starting a family, and hopefully you can reschedule your trip.