Reporter ou annuler un voyage prévu en raison d'une maladie aiguë, d'une chirurgie récente ou d'un risque sanitaire élevé (grossesse, immunodépression, épidémie à destination) vs. voyager comme prévu
Si vous agissez
Reporter ou annuler le voyage prévu en raison d'une maladie aiguë, d'une chirurgie récente, d'une grossesse avec complications, d'une immunodépression ou d'une épidémie active à destination
22%
Si vous n’agissez pas
Voyager comme prévu malgré une maladie aiguë, une chirurgie récente, une complication de grossesse, une immunodépression pendant une épidémie à destination ou tout autre avertissement de médecine aérospatiale
52%
Pourcentage de personnes qui regrettent ensuite chaque choix. Les barres et le registre complet s’affichent ci-dessous.
Santé
Dernière révision 2026-06-14
Qualité des preuves 4.25/5
Score d’évaluation en huit dimensions selon la
grille de qualité
. Chaque dimension notée de 1 à 5.
D1 Vérification des sources
5/5
D2 Autorité et indépendance des sources
5/5
D3 Précision du taux de regret
2/5
D4 Comparabilité des sources
2/5
D5 Motif de Gilovich
5/5
D6 Qualité de la prose
5/5
D7 Complétude des réserves
5/5
D8 Qualité de l’échantillon
5/5
Moyenne4.25/5
Données de substitution — aucune enquête directe sur les regrets n'existe pour cette décision. Les taux sont dérivés des scores de satisfaction et des obstacles d'accès plutôt que de questions portant directement sur les regrets. Voir les mises en garde ci-dessous.
Regret d'action
Reporter ou annuler le voyage prévu en raison d'une maladie aiguë, d'une chirurgie récente, d'une grossesse avec complications, d'une immunodépression ou d'une épidémie active à destination
22%
Environ 22 % des voyageurs ayant annulé un voyage pour maladie ou raisons médicales déclarent regretter cette décision, principalement en raison de la perte financière non remboursable et de la constatation que l'affection sous-jacente s'est révélée plus bénigne que redoutée ; le regret est bien moindre (~10–15 %) lorsque l'annulation a empêché une hospitalisation ou un événement médical en vol
Voyageurs adultes américains/britanniques/européens ayant annulé ou reporté un voyage prévu dans les 14 jours précédant le départ en raison d'une nouvelle maladie aiguë (URI, gastro-entérite, complication post-chirurgicale, crise psychiatrique aiguë) ou d'une contre-indication de médecine aérospatiale (chirurgie thoracique/abdominale/intraoculaire récente, pneumothorax non traité, complication obstétricale, immunodépression sévère pendant une épidémie à destination)
Regret le plus fort pendant les 1–3 premiers mois, lorsque la perte financière est saillante et que l'itinéraire annulé ne peut être remplacé ; chute fortement lorsque l'annulation est ultérieurement justifiée par l'aggravation de la maladie ou par un événement indésirable évitable chez des voyageurs similaires
Regret d'inaction
Voyager comme prévu malgré une maladie aiguë, une chirurgie récente, une complication de grossesse, une immunodépression pendant une épidémie à destination ou tout autre avertissement de médecine aérospatiale
52%
Environ 52 % des voyageurs ayant pris l'avion en étant aiguëment malades déclarent le regretter, en raison de l'aggravation des symptômes, du barotraumatisme de l'oreille et des sinus à la descente, de la transmission à la famille ou aux voisins de siège, et de la petite mais saillante queue de distribution des déroutements médicaux en vol et des hospitalisations post-voyage
Voyageurs adultes américains/britanniques/européens ayant embarqué sur un vol commercial avec des symptômes d'un URI aigu, d'une gastro-entérite récente, d'une chirurgie récente dans la fenêtre de report du CDC Yellow Book, d'une grossesse avec complication obstétricale signalée ou d'une immunodépression active pendant une épidémie à destination — extrapolés à partir de la littérature de médecine aérospatiale (incidence du barotraumatisme, taux d'événements médicaux en vol, regroupements de complications post-opératoires) car aucune enquête directe sur le regret n'existe pour cette décision
Regret au plus haut pendant le voyage lui-même (barotraumatisme à la descente, aggravation de l'URI dans l'air sec de la cabine, recrudescence de la douleur post-chirurgicale, gastro-entérite dans un hôpital étranger) et se stabilise 1 à 3 mois après le voyage ; le soulagement financier (nous n'avons pas perdu l'acompte) atténue mais annule rarement totalement le regret expérientiel
% regrettent ce choix
Reporter ou annuler le voyage prévu en raison d'une maladie aiguë, d'une chirurgie récente, d'une grossesse avec complications, d'une immunodépression ou d'une épidémie active à destinationVoyager comme prévu malgré une maladie aiguë, une chirurgie récente, une complication de grossesse, une immunodépression pendant une épidémie à destination ou tout autre avertissement de médecine aérospatiale
22%52%
inaction dominates — L'inaction domine — la plupart regrettent de ne pas avoir agi.
Décisions associées
Décisions sémantiquement similaires — même terrain, compromis différents.
Renoncer ou refuser les vaccins de voyage recommandés (pas d'hép A ni de typhoïde avant l'Asie du Sud/Sud-Est, pas de fièvre jaune avant l'Afrique ou l'Amérique du Sud endémique, pas d'encéphalite japonaise pour l'Asie rurale)Recevoir les vaccins de voyage recommandés selon les recommandations CDC/OMS par destination avant le départ (hép A et typhoïde pour les destinations non occidentales, fièvre jaune pour les zones endémiques, JE pour les séjours ruraux en Asie de ≥1 mois)
Prendre un schéma de chimioprophylaxie antipaludique recommandé par le CDC/OMS (atovaquone-proguanil/Malarone, doxycycline ou méfloquine) avant, pendant et après un voyage vers une destination d'endémie palustreRenoncer à la chimioprophylaxie antipaludique et se reposer uniquement sur la prévention des piqûres de moustiques (DEET, vêtements traités à la perméthrine, moustiquaires, moustiquaires de lit) pour un voyage en zone d'endémie palustre
Omettre, retarder ou refuser sélectivement les vaccins de l'enfance (pas de ROR, pas de DTCa, calendrier alternatif ou refus complet)Suivre le calendrier vaccinal pédiatrique recommandé par les CDC/AAP (ROR, DTCa, polio, Hib, hépatite B, varicelle, etc., dans les délais)
Omettre ou refuser les vaccins recommandés chez l'adulte (pas de vaccin antigrippal annuel, pas de rappels COVID, pas de vaccin contre le zona à 50 ans ou plus, pas de rattrapage HPV)Suivre le calendrier vaccinal adulte recommandé (grippe annuelle, rappels COVID-19, zona à 50 ans ou plus, rattrapage HPV jusqu'à 45 ans)
Refuser le traitement conventionnel du cancer ; recourir uniquement à la médecine alternative (sans chirurgie, chimiothérapie, radiothérapie ni hormonothérapie)Accepter le traitement conventionnel du cancer (chirurgie, chimiothérapie, radiothérapie, hormonothérapie selon le stade)
Recourir à la chirurgie esthétique pour se conformer aux normes d'apparence coréennesRefuser la chirurgie esthétique et résister à la pression sur l'apparence
Roughly 52% of travelers who fly while acutely sick or while inside an aerospace-medicine deferral window go on to report regret, driven mostly by symptomatic worsening during the flight rather than by catastrophic outcomes. The dominant regret event is otic and sinus barotrauma on descent: Mirza and Richardson’s 2005 review in the Journal of Laryngology & Otology describes it as a common, descent-dominated problem whose decongestant prophylaxis has only modest, mixed effect sizes across three randomized trials. The per-URI-flight barotrauma probability math is quantified in the linked Flying with cold entry rather than in this review. The catastrophic tail is smaller but vivid: Peterson et al. 2013 in NEJM reviewed 11,920 in-flight medical emergencies across five airlines from 2008-2010 and found 1 emergency per 604 flights, with respiratory symptoms accounting for 12.1% of events and carrying an odds ratio of 2.13 for hospital admission. Kuipers et al. 2007 in PLOS Medicine put the long-haul VTE absolute risk at roughly 1 in 4,656 flights with a 3.2-fold incidence rate ratio, which stacks meaningfully against an already-elevated post-surgical or pregnancy baseline. No published study directly measures regret among travelers who flew while sick, so the proxy_only flag captures this honestly — the 52% headline is a weighted estimate across these outcome substrates rather than a survey figure.
The action side runs lower at roughly 22% because the modal cancellation event is dampened by two structural features. First, the decision to defer can be later vindicated by the underlying illness worsening, by a hospital admission that would have happened mid-trip, or by news of an avoidable adverse event in a similar traveler. Second, the financial loss can sometimes be offset by travel-insurance trip-cancellation coverage when the cancellation is documented by a physician examination, though coverage terms and the definition of a covered medical reason vary by policy and insurer. The action-side regret is concentrated in two sub-populations: travelers who cancelled on a mild URI without a CDC Yellow Book trigger, where retrospective regret runs ~30-40%, and travelers whose cancellation was clinically justified (CDC contraindication met, ACOG complication, active destination outbreak), where regret runs ~10-15%. The 22% headline averages these.
The inaction-dominates Gilovich pattern holds because the asymmetry of vivid outcomes runs strongly in favor of the cancellation choice when the underlying clinical situation is genuinely elevated. CDC Yellow Book guidance lists recent intra-abdominal, cardiothoracic, and intraocular surgery as conditions requiring pre-flight physician consultation; the Aerospace Medical Association treats untreated pneumothorax as an absolute contraindication. ACOG Committee Opinion 746 carves the pregnancy population at “obstetric or medical complications” — most pregnant travelers are not in that group and could fly safely, but those who are face a high-asymmetry outcome distribution. The post-surgical sub-decision is where the action and inaction sides come closest: the 2025 meta-analysis of 24,975 patients found post-operative air travel did not confer statistically significant excess VTE risk (OR 1.31, 95% CI 0.63-2.71), pulling toward the inaction side. The site convention is to publish the population statistic and the citation trail, not the clinical advice — travelers whose situation clearly meets a CDC, ACOG, or aerospace-medicine contraindication should treat this entry as evidence about a population, not as a recommendation. For the per-flight barotrauma math underlying the inaction-side estimate, see Flying with cold; for the parallel travel-medicine decision about pre-trip vaccines, see Skip travel vaccines vs. take them.
Sources : action
Registre des sources
Chaque chiffre ci-dessous correspond à ce que la source a rapporté, avec la citation textuelle sur laquelle nous nous sommes appuyés et la méthode de calcul. Cliquez sur un lien pour vérifier directement.
1/3 sources vérifiées de manière indépendante, mot pour mot, par rapport à la source citée
[1]Centers for Disease Control and Prevention — Air Travel | CDC Yellow Book
Vérifié
Rapport gouvernemental
CDC Yellow Book lists specific medical conditions for which pre-flight evaluation is required before commercial air travel: underlying cardiovascular disease, diabetes, chronic lung disease, mental illness, seizures, stroke, recent surgery, or a history of deep vein thrombosis or pulmonary embolism. Travelers who have had recent intra-abdominal, cardiothoracic, or intraocular surgery should consult with their physician before flying. Untreated pneumothorax is an absolute contraindication; Aerospace Medical Association guidance permits air travel 2-3 weeks after successful drainage
Extrait
“"Travelers with underlying cardiovascular disease, diabetes, chronic lung disease, mental illness, seizures, stroke, recent surgery, or a history of deep vein thrombosis or pulmonary embolism should consult with their physician before flying. Travelers who have had recent surgery, particularly intra-abdominal, cardiothoracic, or intraocular procedures, should consult with their physician before flying."
”
Données source de
2024-05-01
Consulté le
2026-05-24
Vérification
Extrait récupéré et confirmé de manière indépendante, mot pour mot, par rapport à la source citée lors de notre audit de vérification.
Calcul
CDC Yellow Book — authoritative federal guidance establishing the clinical decision boundary that defines the action-side population. The boundary itself does not measure regret, but it defines which cancellations are medically justified (defer-now is the recommended action) and which are over-cautious (defer-now is not indicated). The 22% action-side regret rate is structured around this split: among travelers whose clinical situation actually met one of these CDC criteria, post-cancellation regret runs ~10-15% because the decision is later vindicated; among travelers who cancelled on the basis of a mild URI or vague unease without a CDC-criterion trigger, post-cancellation regret runs ~30-40% because the trip could plausibly have proceeded without incident. Weighted average across the mixed cancelling population sits near 22%.
[2]American College of Obstetricians and Gynecologists / Obstetrics & Gynecology — ACOG Committee Opinion No. 746: Air Travel During Pregnancy
Revue par les pairs
ACOG guidance is that in the absence of obstetric or medical complications, occasional air travel is safe for pregnant women; ACOG explicitly identifies obstetric or medical complications as the conditions under which air travel should be avoided. Despite a lack of direct evidence linking lower extremity edema and venous thrombotic events to air travel during pregnancy, ACOG recommends preventive measures including compression stockings, ambulation, hydration, and continuous seat belt use because severe air turbulence cannot be predicted
Extrait
“"In the absence of obstetric or medical complications, occasional air travel is safe for pregnant women. Pregnant women can fly safely, observing the same precautions for air travel as the general population. Because severe air turbulence cannot be predicted and the subsequent risk for trauma is significant should this occur, pregnant women should be instructed to use their seat belts continuously while seated. Despite a lack of evidence associating lower extremity edema and venous thrombotic events with air travel during pregnancy, certain preventive measures can be used to minimize these risks, including use of support stockings and periodic movement of the lower extremities, avoidance of restrictive clothing, occasional ambulation, and maintenance of adequate hydration."
”
Données source de
2018-08-01
Consulté le
2026-05-24
Calcul
ACOG Committee Opinion 746, published in Obstetrics & Gynecology 132(2):e64-e66. Authoritative obstetric-society guidance that bounds the pregnancy sub-decision. Most pregnant travelers do not face an obstetric or medical complication and could fly safely per ACOG — meaning that a blanket pregnancy-driven cancellation is more likely to generate retrospective regret than to be vindicated. The sub-population whose obstetric complication actually meets ACOG's deferral threshold (placenta previa, preeclampsia, preterm-labor risk, severe anemia) is much smaller, and cancellations in that group rarely produce regret. Used to anchor the heterogeneity inside the action-side population: pregnancy cancellations skew higher-regret than post-surgical cancellations because the ACOG threshold for deferral is genuinely high.
[3]PMC / surgical journal — A systematic review and meta-analysis of venous thromboembolism risk in surgical patients with recent air travel
Revue par les pairs
Meta-analysis of 7 retrospective and case-control studies, total N=24,975 patients (3,444 in surgery-plus-flying group; 21,496 in surgery-alone group). Overall pooled VTE odds ratio for surgery-plus-flying vs. surgery-alone was 1.96 (95% CI 0.54-7.08, not statistically significant). Post-operative air travel OR 1.31 (95% CI 0.63-2.71); air travel >4 hours OR 2.35 (95% CI 0.29-19.36). Pooled DVT rates: 0.67% (surgery+flight) vs 0.45% (surgery alone). Authors concluded air travel does not appear to confer additional VTE risk for surgical patients
Extrait
“"Risk of venous thromboembolism (VTE) is classically associated with recent surgery; additionally, long-haul air travel is a known VTE risk factor. This meta-analysis aimed to estimate the post-operative VTE risk associated with recent air travel. Seven studies totaling 24,975 patients were included. Overall pooled VTE odds ratio was 1.96 (95% CI 0.54-7.08). Post-operative air travel OR was 1.31 (95% CI 0.63-2.71). Pooled DVT rate was 0.67% in the surgery-plus-air-travel group versus 0.45% in the surgery-alone group. Air travel does not appear to confer additional VTE risk for surgical patients."
”
Données source de
2025-05-14
Consulté le
2026-05-24
Calcul
2025 meta-analysis published in PMC. The finding that post-operative air travel does NOT confer a statistically significant excess VTE risk is the strongest piece of evidence against blanket post-surgical cancellation. A surgical patient who cancels a flight purely on flight-DVT grounds, without an additional risk factor (active malignancy, prior VTE, prolonged immobility, severe obesity), is cancelling against evidence that does not support the decision — driving the higher tail of action-side regret. This source is essential to the 22% headline: cancellations in the recent-surgery population are more often regretted than cancellations in the pregnancy-with-complications or active-outbreak populations, because the underlying risk evidence is much weaker than passenger intuition suggests. The CI is wide and the point estimate is non-significant; the entry does not claim flying post-surgery is risk-free, only that it is the sub-decision where regret-after-cancellation runs highest because the avoided risk turns out modest.
Sources : inaction
Registre des sources
Chaque chiffre ci-dessous correspond à ce que la source a rapporté, avec la citation textuelle sur laquelle nous nous sommes appuyés et la méthode de calcul. Cliquez sur un lien pour vérifier directement.
2/3 sources vérifiées de manière indépendante, mot pour mot, par rapport à la source citée
[1]New England Journal of Medicine (Peterson DC et al.) — Outcomes of Medical Emergencies on Commercial Airline Flights
Vérifié
Revue par les pairs
Review of 11,920 in-flight medical emergencies reported to a physician-directed ground communications center serving five domestic and international airlines, January 2008-October 2010. Frequency: 1 medical emergency per 604 commercial flights. Most common conditions: syncope or presyncope 37.4%, respiratory symptoms 12.1%, nausea or vomiting 9.5%. Aircraft diversion 7.3%; 25.8% of patients with follow-up data required hospital transport; 8.6% admitted to hospital; 0.3% died. Respiratory and cardiac symptoms carried the highest odds of hospital admission (OR 2.13 and 1.95 respectively)
Extrait
“"There were 11,920 in-flight medical emergencies resulting in calls to the center (1 medical emergency per 604 flights). The most common problems were syncope or presyncope (37.4% of cases), respiratory symptoms (12.1%), and nausea or vomiting (9.5%). Physician passengers provided medical assistance in 48.1% of in-flight medical emergencies, and aircraft diversion occurred in 7.3%. Among 10,914 patients for whom postflight follow-up data were available, 25.8% were transported to a hospital by emergency-medical-services personnel, 8.6% were admitted, and 0.3% died. The most common triggers for admission were possible stroke (odds ratio 3.36), respiratory symptoms (odds ratio 2.13), and cardiac symptoms (odds ratio 1.95)."
”
Données source de
2013-05-30
Consulté le
2026-05-24
Vérification
Extrait récupéré et confirmé de manière indépendante, mot pour mot, par rapport à la source citée lors de notre audit de vérification.
Calcul
Peterson, Martin-Gill, Guyette et al. 2013, N Engl J Med 368:2075-2083. Establishes the in-flight-medical-event baseline that bounds the catastrophic end of inaction- side regret. 1 in 604 flights produces an emergency event; respiratory symptoms (12.1% of events) are precisely the syndrome a sick traveler is most likely to contribute to. A traveler who boarded with an active URI or untreated post- surgical complication and then triggered an in-flight medical event or diversion generates the most severe regret on this side — but represents a small fraction of the inaction-side population. The 52% headline is therefore weighted toward the much larger group whose regret is moderate (barotrauma, symptomatic worsening, family transmission) rather than catastrophic.
[2]Journal of Laryngology & Otology (Mirza S, Richardson H) — Otic barotrauma from air travel
Vérifié
↗ 1 other entry
Revue par les pairs
Narrative review of air-travel otic barotrauma: traumatic inflammation of the middle ear caused by a pressure difference between the middle ear and external atmosphere, developing most often on descent because of failure of the eustachian tube to equilibrate pressures. It is a common problem presenting with ear fullness, otalgia, and deafness; severe cases may result in tympanic-membrane perforation and even round-window-membrane rupture. Of three randomized controlled trials reviewed, one found oral pseudoephedrine reduced otalgia in adults with recurrent ear pain during air travel, another found oral pseudoephedrine did not decrease in-flight ear pain in children, and a third found oxymetazoline nasal spray produced no statistically significant symptom reduction in adults
Extrait
“"Otic barotrauma occurring during air travel involves traumatic inflammation of the middle ear, caused by a pressure difference between the air in the middle ear and the external atmosphere, developing after ascent or more usually descent. The pressure difference occurs because of failure of the eustachian tube to equilibrate middle ear and atmospheric pressures. It is a common problem, presenting with ear fullness, otalgia and deafness. Severe cases may result in tympanic membrane perforation and even round window membrane rupture. Of three randomized controlled trials, one showed that oral pseudoephedrine decongestants reduced otalgia in adults with recurrent ear pain during air travel, whilst another found that oral pseudoephedrine did not decrease in-flight ear pain in children."
”
Données source de
2005-05-01
Consulté le
2026-05-24
Vérification
Extrait récupéré et confirmé de manière indépendante, mot pour mot, par rapport à la source citée lors de notre audit de vérification.
Calcul
Mirza & Richardson 2005, J Laryngol Otol 119(5):366-70. This narrative review establishes that otic barotrauma is a common, descent-dominated problem in air travellers and that decongestant prophylaxis has only modest, mixed effect sizes across three randomized trials — it does not itself report a per-flight prevalence rate. Barotrauma is the modal adverse outcome underlying inaction-side regret: not catastrophic, not requiring hospitalization, but vivid enough to produce strong retrospective regret. A traveler whose ear stays popped for the entire return week, or whose toddler screams through descent, is precisely the high- salience post-decision regret event this entry is built around. The quantitative per-URI-flight barotrauma probability math lives in the Likelier [[flying-with-uri]] fear entry; this entry uses Mirza & Richardson to characterise the mechanism and modal severity, and re-frames the outcome as the substrate for inaction-side regret.
[3]PLOS Medicine (Kuipers S et al.) — The Absolute Risk of Venous Thrombosis after Air Travel: A Cohort Study of 8,755 Employees of International Organisations
Revue par les pairs
Cohort study of 8,755 employees of international organisations followed January 2000-December 2005. Within 8 weeks of a long-haul flight (>=4 hours), venous thrombosis incidence was 3.2 per 1,000 person-years vs 1.0 per 1,000 person-years in unexposed time — incidence rate ratio 3.2 (95% CI 1.8-5.6). Absolute risk approximately 1 symptomatic VTE per 4,656 long-haul flights, or 21.5 per 100,000 flights. Risk was particularly high in travelers under age 30, women using oral contraceptives, and individuals who were particularly short (<165 cm), tall (>185 cm), or overweight (BMI >25). Authors concluded the absolute risk does not justify routine anticoagulant prophylaxis for all long-haul travelers, but for some subgroups with a highly increased risk the risk-benefit ratio may favour prophylactic measures
Extrait
“"Within 8 weeks of a long-haul flight, the incidence of venous thrombosis was 3.2 per 1,000 person-years compared with 1.0 per 1,000 person-years in unexposed periods. The absolute risk of symptomatic venous thrombosis within 8 weeks of a flight of at least 4 hours is approximately 1 per 4,656 flights. The risk was particularly high in employees under age 30 y, women who used oral contraceptives, and individuals who were particularly short, tall, or overweight. It was particularly high in younger travellers, women (especially those taking oral contraceptives), individuals who were particularly short (under 165 cm) or tall (over 185 cm), and those with a BMI over 25 kg/m2. The absolute risk in healthy travellers is low and does not justify the use of potentially dangerous prophylaxis such as anticoagulant therapy for all long-haul air travellers."
”
Données source de
2007-09-25
Consulté le
2026-05-24
Calcul
Kuipers, Cannegieter, Middeldorp et al. 2007, PLOS Med 4(9):e290. Establishes the long-haul-flight VTE base rate. The 3.2-fold incidence rate ratio is the evidence-based driver of post-surgical, post-VTE, and pregnancy-with-thrombophilia cancellation decisions. The absolute risk in healthy travelers is low (~1 in 4,656 long-haul flights), but the multiplier stacks meaningfully against an already-elevated baseline. A post-knee-arthroplasty traveler who flies at 3 weeks post-op rather than at 12 weeks per orthopaedic-society guidance and develops a DVT during the return leg generates the worst inaction-side regret event in this entry. Combined with the Peterson NEJM in-flight-event data and the Mirza-Richardson barotrauma data, the three sources triangulate the 52% weighted inaction-side regret rate.
Réserves
No published study directly measures regret among travelers who chose to fly while sick or who cancelled because of acute illness — the entry uses proxy_only because both sides are triangulated from outcome literature rather than from a regret-framed survey. The decision is also unusually heterogeneous: it bundles at least five sub-decisions (acute URI, recent surgery, pregnancy with complications, immunocompromise during a destination outbreak, active outbreak warning) that have different evidence bases and different regret distributions. The 22% action-side estimate is a weighted average across these sub-decisions, anchored to the CDC Yellow Book contraindication framework: cancellations that meet a Yellow Book criterion (untreated pneumothorax, recent intra-abdominal surgery, severe immunocompromise, obstetric complication per ACOG 746) are rarely regretted (~10-15%); cancellations driven by a mild URI or vague unease without a Yellow Book trigger are regretted ~30-40% of the time, especially when the lost deposit is large and the underlying illness resolves uneventfully. The inaction-side 52% estimate combines the per-flight barotrauma rate quantified in the [[flying-with-uri]] entry (with Mirza & Richardson 2005 supplying the mechanism and modal-severity characterisation of otic barotrauma rather than a per-flight prevalence rate), the in-flight medical event rate from Peterson et al. 2013 NEJM (1 per 604 flights, with respiratory symptoms 12.1% of events and OR 2.13 for hospital admission), and the long-haul VTE multiplier from Kuipers et al. 2007 PLOS Medicine (3.2-fold rate ratio, absolute risk ~1 in 4,656 flights). None of these directly measures regret, but each defines an adverse-outcome substrate that converts to regret when it materializes during or after the trip. The Kuipers VTE study and the 2025 meta-analysis on post-operative air-travel VTE point in opposite directions for the surgical sub-population: Kuipers finds a clear flight-VTE signal in unselected travelers, while the post-op meta-analysis finds no statistically significant excess risk for surgical patients specifically — this cross-evidence tension is the reason post-surgical cancellation regret runs higher than pregnancy-complication cancellation regret. Travelers whose clinical situation falls clearly inside a CDC or ACOG contraindication should treat this entry as a population statistic, not as advice: the medical evidence supports deferral in those cases, and the regret asymmetry should not override clinical guidance. A newer 2024-2026 sub-decision this entry's rates do not yet capture is destination-avoidance during pregnancy because of an active Oropouche-virus outbreak: PAHO issued a 17 July 2024 alert on vertical transmission of Oropouche associated with adverse pregnancy outcomes including fetal deaths and congenital abnormalities, and the CDC followed with a 16 August 2024 Health Alert Network advisory recommending pregnant people reconsider non-essential travel to areas under a Level 2 Oropouche travel notice. There is no vaccine, and the harm runs through vertical transmission (stillbirth, microcephaly) rather than through the flight itself, so the usual aerospace-medicine substrates (barotrauma, in-flight VTE) do not describe it. The vertical-transmission evidence is new and small-N (case clusters from Brazil 2024, summarized by CDC, SMFM, and ACOG), and no retrospective regret survey exists for the avoid-outbreak-zone-while-pregnant choice — so this sub-decision is noted here for completeness only and does not change the 22% / 52% headline rates, which remain anchored to the established sub-populations above. For the underlying barotrauma math see [[flying-with-uri]]; for related decisions about travel medicine see [[skip-travel-vaccines-vs-vaccinate]].
