Pregnant women commonly seek clarification on whether it is suitable to fly during pregnancy because of the physiological and environmental changes associated with air travel.
This paper explores the risks associated with flying during pregnancy and says the main cause for concern in pregnant women should be the possibility of preterm labour or an obstetric emergency developing during flight.
These concerns form the basis of many airline carrier policies that prohibit pregnant women, who are over 36 weeks gestation, from flying. The paper concludes that it would be prudent to avoid air travel from 37 weeks gestation in an uncomplicated singleton pregnancy and if there are significant risk factors for preterm labour (such as multiple pregnancies) women should not fly from 32 weeks gestation. This is also consistent with International Air Travel Association recommendations.
While environmental and physiological changes that occur with alterations in cabin altitude are also raised as a common concerns for pregnant women, the author concludes that this has no direct risk with pregnancy complications. Although there is a reduction in the partial pressure of oxygen during flight, the paper suggests this should not cause a problem in healthy pregnant women.
There are other physiological changes highlighted in the paper that may cause more of an increased risk for discomfort and possible medical complications in the mother, such as motion sickness, which may exacerbate morning sickness, and the duration of the flight with immobility, which increases the risk of deep vein thrombosis (DVT).
Being immobile and cramped for prolonged periods of time is a particular concern to pregnant women as the likelihood of developing DVT, although small, is increased by such conditions. It is generally accepted that prolonged air travel results in a 3-fold increase in incidence of thrombosis, with an additional 18% higher risk for each 2 hour increase in flight duration.
To minimise this risk further, the author offers suggestions to pregnant women flying on medium to long-haul flights (4 hours or longer), including the use of graduated elastic compression stockings and for those with significant risk factors for DVT (such as previous thrombosis or morbid obesity), treatment with low-molecular-weight heparin (LMWH) should be considered for the day or travel and several days thereafter.
The paper rules out some common concerns around the use of body scanners, which use ionising radiation for security checks, suggesting they pose no additional hazard to pregnant women as the dose level used is not considered a substantial risk.
Furthermore, advice is offered to obstetricians to remain aware of conditions that may complicate the pregnancy and could lead to an increase in the risk of problems occurring during the flight. These include severe anaemia, recent haemorrhage, serious cardiac or respiratory disease and recent bone fractures.
Professor Ian Greer, University of Liverpool and author of the paper, said:
“For uncomplicated pregnancies there is no reason to give advice against commercial air travel, and specifically there is no issue with travel in early pregnancy as the main consideration is risk of labour.
“However if the woman has a history of miscarriage or ectopic pregnancy it would be sensible to suggest ultrasound prior to travel to confirm the location and viability of the pregnancy.
“While the risk of developing DVT in flight varies depending on the individual’s risk factors, it is a concern of most pregnant women and there is reasonable evidence to support the use of graduated elastic compression stockings to reduce this risk further.”
Professor Richard Anderson, Chair of the Scientific Advisory Committee, added:
“This paper highlights the main concerns of pregnant women when it comes to commercial air travel and is a useful source of information for obstetricians to be aware of conditions that may complicate a pregnancy.
“Women with any concerns about flying during pregnancy should seek advice from their obstetrician or midwife.”
For more information please contact Caitlin Walsh, Media Officer, Royal College of Obstetricians and Gynaecologists: 020 7772 6300 or firstname.lastname@example.org
The full SIP paper can be found here.
About RCOG Scientific Impact Papers
RCOG Scientific Impact Papers (formerly SAC Opinion papers) are produced by the Scientific Advisory Committee. They are up to date reviews of emerging or controversial scientific issues of relevance to obstetrics and gynaecology, together with the implications for future practice. These documents have been rebranded to raise awareness of the issues in obstetrics and gynaecology discussed in the documents and to more accurately reflect their content and remit of the Committee.