Is air travel in pregnancy safe?

Air travel has become an important part of modern life. Many more women are now employed in jobs that involve frequent flying, and, in fact, most flight attendants are women of reproductive age. In parallel, with the average age of starting a family steadily increasing, many more pregnant women have medical conditions that might be exacerbated by air travel.

Naturally, the most compelling studies on reproductive risks originate from research in flight attendants. In a cross-sectional survey among current and former flight attendants, Lauria et al1 did not detect higher rates of miscarriage associated with active work. They did, however, find higher rates of menstrual irregularities among current flight attendants and 60% higher rates of infertility.1 The lack of risk of spontaneous abortions was corroborated by others.2 However, flight attendants who experienced spontaneous abortions reported working substantially more flight hours (74 hours per month) than did flight attendants who had live births (64 hours per month).2 These data suggest that the occasional flight among healthy pregnant women should not be a concern.3 In contrast, women at higher risk for spontaneous abortions might want to limit their flights.

Pregnancy is associated with increased risk of thromboembolic disease, as is air travel; therefore, their combination has been an area of concern.4 Common advice includes prophylactic mobilization, fluid intake, leg exercises, and use of prophylactic acetylsalicylic acid and compression stockings in the first trimester of pregnancy.4

Freeman et al5 addressed potential risks in late pregnancy; they retrospectively analyzed a pilot cohort of women giving birth to singleton, nonanomalous fetuses. Air travel was not associated with birth weight, shorter gestation, rate of vaginal bleeding, preterm delivery, preeclampsia, or neonatal intensive care admission. There were no thromboembolic events in any of the 118 pregnant air travelers.5

The management of pregnant women who suffer from serious medical or obstetric conditions needs to be individualized. Hypoxia in the cabin might put pregnant women with unstable angina, congestive heart failure, or chronic pulmonary conditions at risk.6 The American College of Obstetricians and Gynecologists advises that pregnant air travelers with medical problems that might be exacerbated by a hypoxic environment who must travel be prescribed supplemental oxygen in flight.3

As a matter of common sense, women at risk of preterm delivery or those suffering from placental pathology should avoid flying in late pregnancy.

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