The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.

Letter to the Editor

Editor, – I was staggered to read the article on 'Flying and thromboembolism' (Aust Prescr 2009;32:148-50) and not see the word 'pregnancy' mentioned once in the entire article.

I think this glaring omission needs to be corrected as there is too much evidence-based research confirming that pregnancy is associated with a significantly raised incidence of deep vein thrombosis on long-haul flights.

This article omits a significant group of travellers and sends incomplete messages to readers.

Richard Porter
Specialist Obstetrician

Authors' comments

Associate Professor Frank Firkin and Associate Professor Harshal Nandurkar, authors of the article, comment:

Increased levels of oestrogen are associated with increased thromboembolic risk during long-haul flights, as discussed in our article, and it is natural to consider this to apply to pregnancy.

It is, however, fundamental that guidance on managing risk factors be based on published evidence or consensus that can reasonably be accessed. In the case of pregnancy there are major publications that do not support an unequivocal assertion of an association with pregnancy in general.

In an article describing life-threatening venous thromboembolism manifested by pulmonary embolism after long-haul flights, there were no cases in pregnant women in contrast to a number of cases in women taking oral oestrogens.1In addition, the most recent American College of Obstetricians and Gynecologists Committee Opinion states there is a lack of evidence of increased venous thromboembolism risk in pregnant women.2


  1. Lapostolle F, Surget V, Borron SW, Desmaizieres M, Sordelet D, Lapandry C. Severe pulmonary embolism associated with air travel. N Engl J Med 2001;345:779-83. .
  2. American College of Obstetricians and Gynecologists. ACOG Committee Opinion No. 443: Air travel during pregnancy. Obstet Gynecol 2009;114:954-5. .