really????
who, when, where?
Some Details are as under
November 15, 2000
Pregnant Pilots And A Look At LASIK Email this article |Print this article
November 15, 2000
by Brent Blue M.D.
Pregnant Pilots
One question I am frequently asked was not an issue when I got my pilot's license 30 years ago -- what about pregnancy and flying? Women were just breaking into the left seat of heavy airplanes and there were not all that many even in general aviation. Now, the aviation community has seen the light and the issue of pregnancy has become a regular aeromedical consideration.
The Basics
There are seven basic issues a pregnant pilot should consider:
Size of the abdomen;
Onset of labor while airborne;
Blood clots;
Hypoxia;
G-force trauma, including seat belts;
Barometric pressure; and
Cosmic Radiation (discussed here).
Size Matters...
The size of the abdomen is the easiest to understand (and visualize). As the abdomen grows, particularly in the last three months of pregnancy, there can be real concerns -- especially in general aviation operations -- whether full range of motion of the yoke can be obtained. This is an individual call for the GA pilot but some airlines restrict pilots to pregnancies of less than 28 weeks (about six months). The airline restriction is mostly based on the pilot's ability to egress the aircraft and to help passengers after a survival crash. Interestingly, the airlines do not restrict obese pilots from flying, and their stomachs can be more prominent than a pregnant women's at term. Egress can also be an issue for a private aircraft owner if the aircraft is not entry/exit-friendly.
...Timing Is Everything...
Obviously, near the end of a pregnancy, a pilot does not want to schedule a three-night trip overseas. Although labor can start anytime, most labors begin with mild contractions or breaking of the amionic sac (bag of water), giving a fair amount of warning before delivery. Still, to be in the middle of a 14-hour flight to New Zealand or in a foreign hotel may not be the most pleasant situation. For a GA pilot, a local flight can easily be terminated or even a cross-country one reversed. Since most women feel "supercharged" toward the end of pregnancy, energy levels are not usually a factor that will hold back a pilot.
Interestingly, most of the "on-the-aircraft" or "back-of-the-cab" deliveries are the easiest. Fast -- or in medical lingo, precipitous -- deliveries are usually very simple and problem-free. They certainly are not the preferred locations but rarely are there any problems whatsoever. If you are ever caught participating in any way in this kind of a situation, remember two things: One, keep the baby warm and dry after the delivery. Two, you do not need hot water for anything!
...Circulation...
Blood clots in the legs and pelvis are not good things but happen to people who are stuck sitting in the same position for long periods of time. This occurs frequently with lengthy travel, whether by air or by auto. Because the enlarging uterus (womb) presses on the venous structures in the pelvis, it restricts blood flow back from the legs. Additionally, the extra estrogen in a pregnant woman's system adversely impacts the body's ability to prevent blood clots. Physical movement is the best prevention if a long flight is mandatory. Ideally, this movement includes walking through the cabin a few times if on an airliner, but even isometric contractions of leg muscles and massaging the legs will help when in a tight GA cockpit for a few hours. Obviously, bidding or planning shorter trips will reduce the risk. (I will not even mention the multiplying effect of tobacco on this problem since everybody already knows you cannot care about a pregnancy if you smoke.)
...Hypoxia...
Hypoxia is not much of a problem for most airline pilots, but it can be for the GA pilot. Experts like Richard Jennings M.D., a former NASA OB/GYN, suggest that oxygen be worn whenever flying at 10,000 feet MSL or more. I tend to be a little more conservative and recommend oxygen at 8,000 feet MSL unless the pregnant pilot lives in a high-altitude location like Jackson, Wyo. Regardless, pulse oximetery is the best option for a pregnant woman to know for sure whether they need oxygen or not.
In general, the fetus will be protected from hypoxia at the expense of the mother by the physiological shunting of oxygen to the fetal circulation via the placenta. Although this may be of marginal benefit, it probably makes a difference in short hypoxic exposures (e.g. 15 minutes while flying through a pass). Since oxygen is cheap and systems can usually be borrowed fairly easily if not owned, why not use it? There is no downside.
...G Forces And Trauma
High G forces such as those done in aerobatics are not recommended. Although no definitive studies have been done in this area, the uterus will move with the body with the G-force movement. More importantly, the pressure of the uterus on the pelvic venous structures during high-positive Gs will induce Gloc (G-force-induced loss of consciousness) much sooner.
The effects of G forces and pregnancy have been studied extensively in automobiles but mainly from a forward sudden deceleration or only with a lap and shoulder harness perspective. They have not looked at five-point restraints as far as I could find. Wearing a simple lap belt is certainly considered safer than not wearing one at all, although many experts suggest not using a shoulder harness during the last three months of pregnancy (put the shoulder strap behind you, just like with a small child). I do not necessarily agree with not using the shoulder harness but I have to defer to the experts. The good news is that studies of pregnant women involved in trauma show amazing resistance to injuries to the fetus unless there are fatal injuries to the mother or penetrating wounds to the abdomen.
Since the fetus is in a liquid world, barometric changes associated with altitude changes are not an issue for a pregnant women or her fetus.
What Do The FARs Say?
There are essentially no regulations from the FAA in the area of pregnancy and flying. There are general recommendations that include: "It is recommended that the airman obtain a release to fly from the physician caring for her pregnancy. It is further recommended that the airman not fly during the last trimester of pregnancy."
There are a lot of old wives' tales concerning pregnancy and even more about pregnancy and flying. Doctors are not immune, either, as I once learned. This doctor advised a sea-level patient to not to come travel to Jackson Hole, at 6,200 feet MSL, because of the possibility of hypoxic harm to the fetus.
I wonder what does he think happens to women who live here?