Activities When Pregnant
We present here some general references pertaining to travel in general during pregnancy and some of the activities that pregnant travelers wish to undertake.
Regarding air travel, we are commonly asked about the danger of cosmic radiation. Of greater concern to us is the propensity toward deep vein thrombosis. And we found quite surprising the article from Australia (Chibber, et al) that showed an increase in prematurity and neonatal complications when pregnant women undertook air travel near term. This new data has yet to be confirmed by other investigators.
Air travel
1. Chibber R, Al-Sibai MH, Qahtani N. Adverse outcome of pregnancy following air travel: A myth or a concern? Aust N Z J Obstet Gynaecol. 2006 Feb;46(1):24-8. Objective: To assess whether air travel elevates the risk of adverse pregnancy outcomes in essentially healthy women with single non-anomalous fetuses at a gestational age greater than 20 weeks. Methods: A retrospective analysis of air travel during the current pregnancy and pregnancy outcome was undertaken in 992 women admitted for delivery over a 12-month period. The study group of 546 (55%) women, of whom 57% were primigravidae, travelled at least once during pregnancy, and were compared with a control group of 447 women (45%), of whom 54% were primigravidae, who did not travel by air. Results: The primigravidae in the study group showed an increased risk of preterm birth, and this risk was statistically significant between the gestations of 34 and 37 weeks (adjusted odds ratio 1.5, 95% confidence intervals 1.2, 1.8); this risk remained elevated after adjustment for covariates. These women's pregnancies were appreciably shorter than those of primigravidae who did not fly (36.1 +/- 0.8 vs. 39.2 +/- 2.1 weeks) and their babies had lower birthweights (2684 +/- 481 vs. 3481 +/- 703 g). and were more likely to be admitted to the neonatal intensive care unit. This group of air travellers is unusual for the uncommonly long and frequent duration of air travel, which is not routinely undertaken in most parts of the world. There were no thromboembolic events complicating any pregnancies. Conclusions: Primigravid women who travel by air appear to be at higher risk for preterm birth. Multicentre large studies are required to confirm or repute these findings.
2. Daniell, Vaughan and Millies. Pregnancy outcomes among female flight attendants. Aviat Space Environ Med 1990 Sep; 61(9):840-4). Flight attendants have been reported to be at increased risk for menstrual abnormalities and for spontaneous fetal loss. This study examined Washington State birth certificates for associations between adverse pregnancy outcomes and maternal employment as a flight attendant. Current pregnancy outcomes (low birthweight, prematurity, low Apgar scores, and abnormal sex ratio) were not significantly related to occupation. Flight attendants reported their preceding pregnancy resulted in a spontaneous fetal loss nearly twice as often as other women (relative risk = 1.9, 95% confidence interval = 1.3-2.7). However, when comparison was restricted to other employed women, the risk was lower (RR = 1.3, 95% CI = 0.9-1.9). A clinically significant pregnancy risk among flight attendants cannot be excluded on the basis of this study, but the apparent excess risk of spontaneous fetal loss in this and particularly in a previous study could be explained at least in part by methodologic limitations.
3. Cone, Vaughn, Huete and Samuels. Reproductive health outcomes among female flight attendants: an exploratory study. J Occup Environ Med 1998 Mar; 40(3):210-6. Recent studies have suggested that female flight attendants may experience increased rates of spontaneous abortion. We conducted a survey of female flight attendants who were pregnant at any time between January 1, 1990, and December 31, 1991 (n = 418) using a mailed self-administered interest survey (response rate, 60 %) and follow-up questionnaire regarding reproductive outcomes and potential risk factors for adverse outcomes (response rate, 64%). The cumulative hazard of spontaneous abortion was 17% when maternal age, smoking, alcohol use, and prior spontaneous abortions were control led for, using a Cox life-table regression model. Of the female flight attendants who worked outside the home, 47 of 321 (15%) experienced a spontaneous abortion, compared with 6 of 73 (8%) who did not work outside the home during the pregnancy period (odds ratio [OR] = 1.91, 95 % confidence interval [CI] = 0.78-4.66). Flight attendants who experienced a spontaneous abortion during their first pregnancy during the study period reported working significantly more flight hours per month during their pregnancy (74 hours per month) than did flight attendants who delivered a live birth (64 hours per month) (Student's t = -3.30, P = 0.002). We conclude that although the results of this study must be considered preliminary because of the relatively low overall response rate (38%), we did not find an overall increased risk for spontaneous abortion among flight attendants, compared with other working women (10%-20%). Women who continue working as flight attendants during pregnancy and those who work relatively higher numbers of flight hours during pregnancy may, however, be at increased risk for spontaneous abortion, compared with flight attendants who do not perform such work.
4. Lyons TJ. Women in the fast jet cockpit--aeromedical considerations. Aviat Space Environ Med 1992 Sep;63(9):809-18
5. Huch R Klinik fur Geburtshilfe, Departement fur Frauenheilkunde, Universitatsspital Zurich. Z Arztl Fortbild Qualitatssich 1999 Oct;93(7):495-501 Abstract: Women who fly during pregnancy, whether as passengers or crew, continue to fuel the debate over the potential impact on pregnancy outcome and fetal development, the two risk factors most commonly invoked being relative hypoxaemia due to the decreased cabin pressure and, more recently, cosmic radiation. On both theoretical and experimental grounds (altitude physiology and studies in pregnant women during flight), commercial flight poses no threat to the fetal oxygen supply in a normal pregnancy. As for cosmic radiation, only theoretical estimates are available of flight crew exposure: if annual doses approximate to background at ground level (3-5 mSv), the dose received during an individual pregnancy can be estimated from the fraction of annual flight time spent while pregnant. It is doubtful whether any epidemiological study could ever confirm or refute this theoretical estimate of a low increase in risk. Many airlines have opted to allow pregnant crew to continue flying. There is thus little if any ground for advising against passenger flight in pregnancy. Flying is probably the safest and most comfortable way to travel long-distance in pregnancy. The few relative contraindications include flying close to term, a history of miscarriage and premature delivery, heavy smoking, severe anemia, cardiopulmonary disease, and a serious fear of flying.
6. Blumen IJ, Rinnert KJ Altitude physiology and the stresses of flight. Air Med J 1995 Apr-Jun;14(2):87-100
7. Rayman RB Passenger safety, health, and comfort: a review. Aviat Space Environ Med 1997 May;68(5):432-40. Since the birth of aviation medicine approximately 80 yrs ago, practitioners and scientists have given their attention primarily to flight deck crew, cabin crew, and ground support personnel. However, in more recent years we have broadened our horizons to include the safety, health, and comfort of passengers flying commercial aircraft. This will be even more compelling as more passengers take to the air in larger aircraft and flying longer hours to more distant destinations. Further, we can expect to see more older passengers because people in many countries are living longer, healthier lives. The author first discusses the stresses imposed by ordinary commercial flight upon travelers such as airport tumult, barometric pressure changes, immobility, jet lag, noise/ vibration, and radiation. Medical considerations are next addressed describing inflight illness and medical care capability aboard U.S. air carriers. Passenger safety, cabin air quality, and the preventive medicine aspects of air travel are next reviewed in the context of passenger safety, health, and comfort. Recommendations are addressed to regulator agencies, airlines aircraft manufacturers, and the aerospace medicine community.
Cruise travel
1. Brewer PA, Barry M. Survey of web-based health care information for prospective cruise line passengers. J Travel Med. 2002 Jul-Aug;9(4):194-7. BACKGROUND: To determine the availability of information concerning medical care available onboard the ships of the major cruise lines operating in the North American market. METHODS: The Web pages of the 16 members of the International Council of Cruise Lines were explored for the following types of information: ease of access of medical information, qualifications of medical personnel, description of medical facilities on board, maximum distance from nearest port, telemedicine capabilities, maximum gestational age and minimum infant age allowed, medical insurance information, and links to recognized guidelines for medical care on cruise ships. RESULTS: Seven cruise lines had minimal or no medical information at all. No cruise line presented information about medical evacuation or telemedicine services. Ten cruise lines had no information on maximal gestational age and 11 did not specify minimum infant age. No site offered a link to guidelines concerning medical facilities on board. CONCLUSION: The advanced age of the average cruise ship passenger and the isolation of the cruise environment create a need for high quality medical facilities and staff onboard cruise ships. The lack of detailed information concerning medical care available onboard makes it difficult for the average prospective passenger, who has health concerns, to make an informed decision as to choice of cruise line and itinerary. Cruise lines should correct this by including more information regarding medical services as well as links to other cruise health Web sites.
2. For general information regarding medical facilities aboard cruise vessels, we refer you to the web pages of the International Council of Cruise Lines at http://www.iccl.org/policies/medical.cfm and http://www.iccl.org/policies/medical2.cfm.
Scuba
1. Morales M, Dumps P, Extermann P. [Pregnancy and scuba diving: what precautions]? J Gynecol Obstet Biol Reprod (Paris) 1999 May;28(2):118-23 [Article in French]
2. Gustavsson LL, Hultcrantz E. [Medical aspects of diving--a sport for both women and men]. Lakartidningen 1999 Feb 17;96(7):749-53 [Article in Swedish]
3. Camporesi EM. Diving and pregnancy. Semin Perinatol 1996 Aug;20(4):292-302. Scuba diving during pregnancy has increased in incidence as a result of substantial growth in the number of young females attracted to sport diving. This review summarizes the physiological changes induced by immersion, diving and decompression, on male and female divers. Furthermore, it extends to literature review, in animal models, of the susceptibility of a pregnant animal to diving decompression injury. Publications regarding reports of diving injury in pregnant humans are also reviewed, comprising very recent material from the sport diving community. It is concluded that there is no countraindication to diving for the normal, healthy, nonpregnant female. However, pregnant females should refrain from diving, because the fetus is not protected from decompression problems and is at risk of malformation and gas embolism after decompression disease. It is prudent to advise pregnant patients of the increased risk of diving problems for the fetus during pregnancy. However, should a woman have completed a dive during early pregnancy because she was unaware she was pregnant, the present evidence is not to recommend an abortion, because several normal pregnancies have been documented even if diving is continued. Snorkeling can still be practiced during pregnancy, but scuba diving should be discontinued until after the birth period.
4. Sauceda Gonzalez LF, Gavino Gavino F, Ahued Ahued JR, Hernandez Gonzalez Y. [Scuba diving and pregnancy. A case report and review of the literature]. Ginecol Obstet Mex 1995 May;63:202-4 [Article in Spanish]
5. Cresswell JE, St Leger-Dowse M. Women and scuba diving. BMJ 1991 Jun 29;302(6792):1590-1
6. Newhall JF Jr. Scuba diving during pregnancy: a brief review. Am J Obstet Gynecol 1981 Aug 15;140(8):893-4
7. Bolton ME. Scuba diving and fetal well-being: a survey of 208 women. Undersea Biomed Res 1980 Sep;7(3):183-9. Scuba diving is an increasingly popular sport among women of childbearing age. It causes physiological changes that are possibly lethal or teratogenic to the fetus. The subject of diving during pregnancy is seldom mentioned in diving courses, however, and few obstetricians are familiar with the physiology of diving. The study employed mailed questionnaires for description and comparison of the extent of diving and obstetric and fetal outcome of 208 women divers, 136 of whom dived during one or more pregnancies. Depths to which these women dived averaged 42.6 ft; 24 women, however, reported dives deeper than 99 ft during the first trimester. I analyzed the prevalence of six specific fetal complications and found that the frequency of birth defects was significantly greater among children from pregnancies during which women dived (P < 0.05) but was within the range for the general population.
8. Revel A, Zohar N, Lincoln R, Sherman D. [Underwater diving during pregnancy]. Harefuah 1995 Jun 1;128(11):707-10 [Article in Hebrew]
9. Jennings RT. Women and the hazardous environment: when the pregnant patient requires hyperbaric oxygen therapy. Aviat Space Environ Med 1987 Apr;58(4):370-4
10. Whitaker AJ, Bodiwala GG. Immediate management of diving emergencies. Br J Sports Med 1982 Jun;16(2):102-6 |
