Women and Diving.

Introduction
One problem that women have is discussing some problems with men, unless of course that man is their Doctor or partner.
There may be some problems that a female member may wish to ask questions about but is too embarrassed to ask her instructor, especially if the instructor happens to be male.
Whether the instructor has the answer is another question but if a female instructor has some insight to the dilemma that the trainee is pondering over then further embarrassment will hopefully be avoided.

This paper is taken from an excellent article by Derek Nelson, which appeared in the September 95 edition of "Scottish Diver". In some cases it is unashamedly a straight copy of that article as it put over the various points in a simple and easy to understand way. However have also used other sources for any relevant information and I have included these sources in a reference section at the end of this paper.

If however there are still questions that require an answer then it may be possible to have your questions answered by the ScotSAC medical referee. To do this you may have to discuss any questions with your Branch Diving Officer, who could via the ScotSAC Head Office contact the Doctor in question.
Always remember though that if it is a simple yes or no answer you are looking for then speak to a female member of your branch. And finally also remember that if your male colleagues appear to be ignorant of your plight, please remember that they do not have some of the "problems" that women have, or they to may be embarrassed by your questions.

Menstruation
During the 3 to 5 days of menstruation a woman may loosen between 50 to 150cc of blood and cellular debris, accompanied with hormonal changes, fluid shifts, weight gain and possible pre-menstrual tension.
This loss of blood has prompted fears that women diving on holiday may attract sharks. There is no support for such a belief, Indeed "old blood" in the menses may even act as a shark deterrent Statistics on shark attacks from around the world show women have a much lower instance of attack
In a recent Diving Diseases Research Centre (DDRC) study 57% of women reported suffering from fluid retention; this being a result of hormone changes before and during menstruation.
There exists a theoretical possibility that such fluid retention may be a predisposing factor in Decompression Sickness (DCS). In the above study, the most comprehensive to date in the U.K., 34% of women reported impaired reactions and overall 71% reported suffering from Pre-menstrual Tension (PMT).
The same study showed that only 7% refrained from diving whilst menstruating, with another 11% adopting more conservative dive profiles.

Some women have significant difficulties with cramp, nausea, abdominal pains and vomiting during this time.
This will obviously impair their diving activity and if these symptoms are present they should avoid diving at this time.
Those women not prone to the above conditions should consider observing more conservative dive profiles than normal while they are menstruating.
Another consideration when diving whilst menstruating is that there is an increased swelling of the Mucosal Membrane. This may make the equalising of the ears and sinuses more difficult and should this occur it would be best to avoid diving until the condition clears up.

Contraception.
The contraceptive pill can cause an increased coagulation on the blood in some women, especially those over 35 and in those who are overweight or smokers. This could have DCS complications but it should be emphasised that there is no established link between taking the pill and any possible increases to DCS susceptibility. As yet it is unknown if any research into diving whilst taking the pill has been carried out.

Information into the Cap or Diaphragm type of contraception and diving is equally scarce, though another recent surveys show that 12% of women diving with this form of contraception noted some problems. These problems seemed to range from discomfort to difficulty in retrieving the diaphragm after the dive. There is also no indications of problems being caused by the creation of an artificial airspace created by the use of diaphragms.

Tampons.
There has to date been no research carried out on the use of tampons and diving. Similarly there seems to be no problem with any air spaces caused by the insertion of a tampon.
It may be reassuring to note that there has never been a case of air embolism via the uterus recorded during diving whilst using a tampon, though there has been recorded cases of air embolism via the uterus but this was from insufflation of the vagina during oral sex in pregnant women (not really diving related, well not SCUBA Diving anyway).

Breast Implants
Again this is a subject which has not been greatly researched, but what research that has been done on silicon gel and saline implants has shown that bubbles can form during a dive causing an increase in volume of up to 40% but these bubbles can be tolerated quite safely and asymptomatically during normal recreational diving, however it is not recommended that women with Breast implants carry out decompression diving.
Recently some reports indicate that silicon gel implants can leak which can cause some nasty side effects. The outcome of a diver who has leaking implants being more susceptible to DCS is as yet unknown, though is the diver is aware of leakage they should refrain from diving.

Decompression Sickness (DCS)
Over the years there has been a number of studies on whether gender causes a difference in the susceptibility to DCS. Most of these surveys are either non- conclusive or contradict a previous survey, where one study shows that women may have a 3.3 fold increased susceptibility another study claims that there is no difference.
Another study of 2,250 divers covering 450,000 dives showed that men are more susceptible than women to DCS, at the same time however it was also noted that women are more conservative when it comes to their dive profiles than men are, who tend to be more aggressive with their profiles.

Pregnancy
In 1980 Bolton published the results of his study of 208 women into, "SCUBA Diving and Foetal Well Being". He concluded from this that women who dived during pregnancy did have (5.5%) more birth defects than those who didn’t. He did however note, that this number was very small and not conclusive.

Turner & Unsworth followed this in 1982 by a paper into Intrauterine Bends, and detailing some of the deformities witnessed after birth. The implications from these studies is clearly "do not dive if pregnant"

If diving is continued during pregnancy, the question has to be asked about the possible problems

Foetal Development
The foetus up until the fourth month of pregnancy is smaller than a mouse. The woman may not even realise she is pregnant at this time. A small bubble formed during DCS can have a catastrophic effect, as witnessed by Turner & Unsworth.
It is unclear as to what effects increased pressure on an embryo will have. Similarly, whilst it is known an embryo is more sensitive to low partial pressures of Oxygen than the mother. The outcome of the embryo being subjected to increased partial pressure of Oxygen and Nitrogen are presently unknown.

Potential problems in diving for the foetus
Hypoxia; A consequence of many non-fatal diving accidents is hypoxia. i.e. salt water aspiration or near drowning. As all ready mentioned the foetus is much more sensitive to the reduction of the partial pressure of Oxygen.

Hyperbaric Oxygen; Diving increases the partial pressure of oxygen being breathed. In addition the diver may require Oxygen therapy in the event of DCS. Many first aid situations within and outwith diving also warrant the administration of 100% normobaric Oxygen (normobaric oxygen = 0.21% O₂)

Great care is taken to avoid high concentrations of oxygen being administered to premature babies as this may cause blindness. It is probable that the eyes of unborn babies are equally as sensitive to this problem.
In addition the raised partial pressure of oxygen in the blood of a new born child acts to close the duct that allows blood in the foetus to bypass the lungs. There may be danger of premature closing of this duct while the foetus is still unborn, due to hyperbaric Oxygen treatment given to the mother.

Decompression Sickness in the Foetus
Studies using animals have shown that that exposure to hyperbaric conditions may cause birth abnormalities or still births. As previously mentioned Intrauterine Bends may have catastrophic consequences.

There are theoretical reasons to believe that the physiological changes during pregnancy result in an increased susceptibility to DCS. In addition Doppler studies have shown regular "silent bubbles" are present in the blood after non-decompression dives.
Again studies with animals, which have a placenta similar to that of humans, showed bubbles present in the foetus after dives shallower than 30 metres and within decompression limits. Considering the effects of a few bubbles in the foetal circulation this is of considerable concern. These studies have also shown increased rates of spontaneous abortion, birth defects and still births.

One problem however is whether the studies involving animals are relevant to humans. for obvious reasons it would be highly unethical to carry out similar studies on pregnant women.

The studies have provided different results which help to confuse the issue, what is unknown is whether the studies also took into account a variety of other factors like age, area lived in, diet, job etc.
If you have discovered that you may be pregnant and have carried out any diving, a visit to the obstetrician for an ultra sound scan may allay any fears about the unborn child.

Towards the end of the pregnancy some women leak fluid into the vagina through the membrane surrounding the foetus. This often goes unnoticed by the mother. There is the remote danger that sea water may get into the womb (assuming the mother is wearing a Wetsuit/Semi-dry suit) and cause infection or premature labour. The same risk however, exists in a swimming pool.
The obvious point to raise here however is would the expectant mother actually fit into their Drysuit /Wetsuit /Semi-dry suit. And if she was able to wear her suit, where would she put the weightbelt if it would fit

The conclusion must be therefor that if the diver finds that she is pregnant, then the sensible thing to do would be to stop diving until after the birth. In some cases this may not be acceptable to the diver in question. If the diver feels that she must dive then shallow profiles (20 metres) and bottom times well within the limits would be suggested.

It must be added however that the Branch Diving Officer who is overall responsible to the wellbeing of branch members may recommend that all diving is stopped.

Further Reference
M.S.T. Leger Dowse; Men and Women in Diving. Published by DDRC (1995)

M.E. Bolton; SCUBA Diving and Foetal Well Being (1980)

Turner & Unsworth; Intrauterine Bends. Published by The Lancet. (1982)

M.S.T. Leger Dowse; Women and Diving, parts 1-4 (1995)

R. Dunford; Women and DCS. Published by Diver’s Alert Network (DAN) (1994)

S. Bangasser; Medical profiles of the Woman SCUBA diver. Published by NAUI (1978)

J. Lipmann; Deeper into Diving. (1990)

R.Vann; Mammary Implants in Divers. Published by SPUMS Journal. (1987)

J. Betts; Diving and the Unborn Child. (1985)