Expert: Roberto Gomes - 12/23/2009

Question
QUESTION: In an previous answer you stated "All pregnant women, though, should steer clear of flying in an unpressurized cabin." and I have seen this in other places.  Where did this idea come from and why?  If the unpressurized aircraft is flying at less than 8,000ft then the pressure difference will be less than in an airliner with the cabin altitude at 8,000 ft.

ANSWER: Dear Mel,

If you read the whole answer you noticed that this reccomendation came from the American College of Obstetricians and Gynecologists (ACOG).

The problem is with a pressurized aircraft, when it gets de-pressurized.

Best Regards,
R. Gomes

---------- FOLLOW-UP ----------

QUESTION: If you read the whole question you would have noticed that in your original answer you said that the problem is in flying in unpressurized aircraft, but travel on an airline (pressurized) is fine, while in your answer to me you said the problem is with pressurized aircraft, which is the exact opposite of your first answer.  

De-pressurizing is a normal part of descent and landing, unless you are talking about an unexpected loss of pressure at altitude, which would be bad, but you and the other recommendations I've found said that flying in pressurized aircraft is fine.

Please let me clarify my question and please don't rush through it.
Why does the American College of Obstetricians and Gynecologists recommend against flying in unpressurized aircraft, when an unpressurized aircraft flying at an altitude of less than 8,000 ft will have a lower cabin altitude (and less pressure change) than on an airline.  The unpressurized aircraft will also have no risk of a rapid decompression.

ANSWER: The major risk for pregnant women is the sudden depressurization.

And what ACOG referred to when saying that "All pregnant women, though, should steer clear of flying in an unpressurized cabin" is that the heart rate and blood pressure will increase to help the body with its oxygen intake.

You can contact them to clarify your doubts even further at:

American College of Obstetricians and Gynecologists
PO Box 96920
Washington, D.C. 20090-6920
(202) 638-5577

Best Regards and Happy Xmas!
R. Gomes

---------- FOLLOW-UP ----------

QUESTION: If you don't know the answer, why don't you just say that you don't know?

Your reply is vague and contradictory.  If the risk is because of the risk of a rapid decompression then there would be NO risk of this on a non pressurized aircraft.  However, originally you had a problem with an non pressurized aircraft, and I was trying to find out why.  Changing the subject is not an answer, and telling me to contact someone else because of my "doubts"/ your non answer is again, not an answer.

For example: "And what ACOG referred to when saying that "All pregnant women, though, should steer clear of flying in an unpressurized cabin" is that the heart rate and blood pressure will increase to help the body with its oxygen intake."  This sentence does not make sense.  Heart rate and blood pressure increasing to help with oxygen intake is not specific to a type of aircraft or driving to Denver for that matter.  So, what does that have to do with pressurized vs. non pressurized aircraft?

Answer
Many doctors have advised expectant mothers to avoid flying at high altitudes in non-pressurized aircraft to minimize the possibility of miscarriage resulting from insufficient oxygen reaching the foetus.

This forum is about air travel and not a medical advisory. What I got came from researches over the various procedures in place on the airlines.

You're always welcome to disagree, but if you need a clear and concise medical evaluation, please refer to the contact provided. For sure they are more experts in this field than the volunteers on this site.

Best Regards,
R. Gomes