Dr Jules Eden, dive medicine specialist and founder of e-med, answers divers' questions - as published in Sport Diver magazine:
Q - We are due to go on a holiday booked prior to finding out that I was pregnant. I have since had an incomplete miscarriage and am due to have an Evacuation of Retained Products of Conception (ERPC). I have been told that I will not be able to swim for four to six weeks after the procedure due to the potential for infection but would it be OK to dive in a drysuit?
A - Sorry to hear that, not a pleasant experience for anyone to have to go through. Infection is one of the risks after this procedure so wetsuit diving would be out for the sort of time period you mention. But I don't see any reason you shouldn't dive in a dry suit - the infection risk is negated, and it would probably be a good idea to have a holiday after the trauma of an ERPC. There are similar advisory delays for diving after a normal delivery or a Caesarean. Basically once the uterus has shrunk to its normal size, vaginal discharge is negligible, any wound has healed sufficiently and the woman is sufficiently recovered, then diving can resume.
Q - I have a 9 month old baby who I am still breastfeeding. My periods have not yet returned following this delivery. Last week I travelled abroad and dived 6 dives to a max of 28 metres over a two day period. However, I have just found out since then that I am pregnant again and could be anything between 4-9 weeks. Clearly I didn't realise that I was pregnant at the time of my diving and I didn't have any symptoms of the bends but I am concerned about possible effects on the foetus. I would be grateful for your advice.
A - There’s a dearth of data on diving in pregnancy. There are some case reports in which pregnant mothers with carbon monoxide poisoning were treated with hyperbaric oxygen in a chamber without adverse effects on the foetus. Conversely, many animal (and some human) studies have noted an increase in the incidence of foetal abnormalities and spontaneous abortions in those who dived whilst pregnant.
Very early in pregnancy, up to 2 weeks or so, there is no effective blood circulation between the placenta and foetus – so problems are unlikely. Once such a circulation develops, there might be. In adults, rogue bubbles are cleared by the lungs as they circulate throught the blood. In the womb, bubby lacks this “bubble filter” and there are theoretical concerns that a diving mum might transfer bubbles to the developing foetus which cannot clear them. This might lead to heart or lung malformations.
However, so many other variables are involved that it is impossible to extrapolate causality from the information we have. Although we no longer recommend diving during a recognised pregnancy, there is no solid scientific data to prove that diving is dangerous to the foetus.
Q - We are due to go on a diving holiday, which was booked prior to finding out that I was pregnant. I have since had a incomplete miscarriage and am due to have an ERPC (Evacuation of Retained Products of Conception). I have been told that I will not be able to swim for 4-6 weeks after the procedure due to the potential for infection but would it be OK to dive in a drysuit?
A - You poor thing, this must be a very difficult time for you. These situations do arise tragically often so this goes out to all other women in a similar predicament. Basically, when a miscarriage occurs, remnants of the pregnancy can be left in the womb, and these need to be removed at some point to stop further bleeding or infection developing. The “retained products” are either scraped out with a curette after the cervix has been dilated, or sucked out via a plastic tube. This sounds awful, but in reality is usually a 5-10 minute procedure, performed under a general anaesthetic, which greatly reduces the risks of miscarriage complications. Normally you’re in and out of hospital in a day, and most women are back to their usual activities within 72 hours. I guess diving ain’t usual though. Light bleeding can occur for up to a fortnight afterwards, so sanitary towels are advisable, making diving a bit impractical. I think that once the bleeding has ceased, diving in a drysuit would be fine.
Q - I wonder whether you would be able to give me some advice. I have a friend who has just found out she is 4 - 5 weeks pregnant (max. 6 weeks) and we are due to go on a scuba diving holiday next week. Please can you confirm the following:-
1) Can you still dive if you are pregnant?
2) If you can still dive, is there a maximum depth you can go to?
3) Are there any restrictions?
4) If you can still dive at what point during the pregnancy must you stop?
A - Sadly for your friend the answers are no, no, yes and stop now.
I have been into this at length on a few occasions and you can read it in the archived copy on www.e-med.co.uk Click on the dive medicals icon and then find the Sport Diver click through.
It’s under “women’s problems”, although pregnancy shouldn’t be classed as a problem.
In a nutshell, if she dives there is always a risk of a bend. That bend could cause a nitrogen bubble in the developing foetal nerve tissue. If it wasn’t diagnosed in mum, then it could affect the newborn child.
I know a lot of this is theoretical and there is no real case controlled studies to support it. But, hey we doctors have ethics you know. Or at least some of us do.
There have probably been thousands of dives performed by pregnant divers who either didn’t know it or didn’t care, and I’m sure they all ended well with no problems to mum or the child when it was born. But if she knows she is pregnant then it really just isn’t worth diving for the next 9 months or so, as the lifetime of guilt if something were to go wrong just wouldn’t be bearable.
Sorry to bring bad news but I’m sure she’ll take it well.
Q - I have been given your name by one of my diving instructors who suggested you may be able to help with my query.
I am currently learning to scuba dive and will be completing the open water section in Turkey during w/c 24.9.01. I am aware that you should not dive whilst pregnant, but I had been planning to try and get pregnant during that holiday. My period started yesterday (earlier than expected) so effectively I could be 3 weeks pregnant (by LMP) by the time I dive. My history is that I've had 2 miscarriages in the last year and I'm 37 next month.
Could you let me know if diving at that early stage could cause risk to the embryo which presumably would just be implanting if I was successful, or wouldn't it make any difference at such an early stage?
A - I know there are some real sickos in my profession but thankfully none have plunged to the depths of seeing the effects of DCS or gas emboli in the developing human fetus. Or even in goats for that matter.
The answer is we don't know, and it's because we don't know that I suggest you really don't risk it. Sure there are plenty of people right now diving away blissfully unaware that they are pregnant, and everything turns out just fine. And I'm also sure there have been cases of pregnant women getting DCS who have a normal healthy intelligent child. But, and it's a huge but, if something happened when you were diving and you miscarried or even got pregnant and there was an abnormality in your child 9 months later, you would never forgive yourself would you.
That's the way I see it. The logic is psychological not medical, but often enough that is more important.
Other doctors may disagree saying the chances of getting a case of DCS in what amounts to a collection of cells at this early stage of pregnancy are nil. Again plenty of people have unprotected sex and dive with a laissez faire attitude to getting pregnant, but I feel if you are deliberately planning a child you should just temper your lifestyle for the time it takes to do so. I assume you are not drinking excessively or smoking 20 a day "just in case" and the same goes for diving.
On non-diving note, do make sure you are taking folic acid on a daily basis as this is good at preventing "neural tube defects" such as spina bifida and watch out for the food you eat in Turkey. A case of salmonella from soft cheese or uncooked eggs is devastating at any stage of pregnancy.
Q - I'm going diving in the Galapagos Islands next month with my wife who has happily found out that she is 6 weeks pregnant. My question is will it be safe for her to travel there and maybe also take in a trip to the Amazon as we have some extra time in Equador, or should we be rethinking the whole destination?
A - I don't think you have to necessarily cancel the trip at this stage, but you may well have to adapt it to fit in with your wife's pregnancy. The main thing is with immunisation and malaria prophylaxis.
Pregnancy is divided up into 3 thirds called trimesters, and the most crucial time for the development of your child is in the first trimester. It is during these 12 to 14 weeks that all the sensitive embryonic developments of limbs and other organs occurs, and anything that can have an effect on the fetus here will cause far more serious problems later. 2 of the vaccines your wife should have for an extensive trip to Equador can theoretically cause problems if given in the first trimester. These are Yellow Fever and the newer Hepatitis A shot. Now, she will mainly be at risk of getting Yellow Fever if you both go down to the Amazon, as it is a disease spread by mosquitoes that are lowland and forest based. So I suggest that if she hasn't previously been vaccinated against this (within the last 10 years) then she should avoid it and that you both stay away from the Amazon Basin, but head to higher ground if you have some spare time. I can recommend Banos south of Quito. She is unlikely to encounter Yellow Fever in the Galapagos, so that should be fine. As for the Hepatitis A shot, I would recommend she have the old style immunoglobulin as that is much safer in this trimester, but sadly it is getting harder for us doctors to get hold of as the manufacturers are annoyingly ceasing its production in favour of the more expensive alternatives.
She will need to take malaria prevention whilst away, but for that part of Equador the combination of chloroquine and paludrine should be fine, and they are both safe to take in pregnancy.
Other issues in her case are that whilst you are enjoying the close up animal encounters and diving with hammerheads, she may well be throwing up in a bucket every morning. Morning sickness is a problem up to 14 weeks when levels of the hormone HCG drop, and as she will be also on a boat for a lot of the time then it might be an idea to take antiemetic tablets with her. Probably the best ones in her circumstances are called metaclopramide and her doctor should give you a scrip for these.
As she doubtless knows she must avoid certain foods at this time, especially undercooked eggs and soft cheeses. I suggest that you both learn the Spanish for these items, so when you are presented with a plate of food of ambiguous origin, you can ask the chef quickly and politely if it contains these products. It beats entertaining other diners with your chicken impressions as you try to fathom the food's contents in sign language.
She cannot dive of course but snorkelling would be fine at 10 weeks of pregnancy. I think the real message here is that if you are a keen traveller then get both Hep A and Yellow Fever in early as they both last 10 years and similar problems with a later pregnancy wouldn't occur.
Q - My wife and I are both keen divers. We recently went and dove together in Key Largo. My wife at the time was about 2 1/2 months pregnant. We dove one spot to 18 m, but otherwise spent the week no deeper than 9 m. We looked into this before our trip, and could not a definitive answer on diving and pregnancy, other than "don't dive if you are pregnant just because we don't know what else to say." My instructor suggests that you might be able to come up with a more reasoned analysis of this issue which is probably of use to many of your readers. So, here it is:
What are the risks involved (if any) of SCUBA diving while pregnant to the mother and the fetus? To the extent there are risks, can the be mitigated by not exceeding a certain depth or by not diving at all during a certain part of the pregnancy?
A - Here's why you cannot dive if pregnant, or even trying to get pregnant. One of the issues with diving is that for all the tables and dive computer algorithms we have, there is always a chance, however remote that you could get a bend. I have seen divers, who have stuck to the limits of no decompression diving, and still get bent. This is because there are many variable factors to take into account. Now we all take the risk and dive without problems as this decision concerns ourselves only, but the question with pregnancy is what could happen to the unborn child if a problem occurred.
Nitrogen bubbles are easily absorbed by neuronal or nerve tissue. If a pregnant diver got a hit but it stayed undiagnosed as it does often, then the foetus could easily have a neurological DCS and you wouldn't be aware of it.
This could cause problems later in the unborn child as the nervous system developed in pregnancy. Now I know that a lot of this is speculation as there is not a lot of research on the matter because it wouldn't get past the ethics committee.
Of course there are also a lot of women who have dived whilst not realising they were pregnant and without any problems, but the key issue is that if you dived, had a bend and there was a deformity in your child when born, was it due to the nitrogen or was there some other cause. That question could never be answered, but the fact that if it was the nitrogen, it could have been avoided by not diving and there would always be a level of guilt in the mother.
So I always say to just leave it for 9 months, as this is not that hard when the downside could be disastrous.