Can I go through airport security scanners while pregnant?

The verdict

Yes, and the government says so directly. GOV.UK's guidance on your rights at the airport states that you may be asked to have a body scan with security scanning equipment even if you are pregnant, and that children can also be asked.

The same guidance sets out your alternative in the next line: you can ask for a private search instead of a body scan, which it describes as a thorough hand search where you may be asked to loosen or take off some clothing.

Both halves matter. There is no exemption for pregnancy, and there is an alternative available on request. If you would rather not be scanned, you do not need a reason and you do not need a letter; you need to ask.

The dose question

The worry underneath this question is radiation, and it is worth being precise about what was measured and when.

The Department for Transport records that the then Health Protection Agency, whose functions now sit with the UK Health Security Agency, conducted an official assessment of the x-ray backscatter scanner in use at some UK airports and found that the dose of ionising radiation received from deployed backscatter scanners is the equivalent of that received naturally through just two minutes of flying at high altitude.

That comparison is the useful part. Anyone flying is already exposed to a slight increase in cosmic radiation for the whole duration of the flight. If the scanner dose equals two minutes of that, the scanner is a rounding error against the journey it is letting you take.

It is also worth knowing that scanner technology has moved. Millimetre wave scanners, which use radio waves rather than x-rays and involve no ionising radiation at all, are now the common type at UK airports. The DfT statement above relates to backscatter machines specifically.

The walk-through arch and the wand

These are different machines from body scanners and get confused with them constantly.

A walk-through metal detector arch and a hand-held wand work by generating a magnetic field and detecting the disturbance metal causes in it. Neither emits ionising radiation. They are the same physical principle as the metal detectors used in shops and stadiums.

GOV.UK's airport guidance addresses hand-held scanners in the context of headgear, noting that if you are wearing headgear for religious or cultural reasons you can ask for it to be checked using a hand-held scanner. It also addresses implanted devices, saying you can ask for a hand search if you have an implantable cardioverter defibrillator, that scanning devices and metal detectors should not cause a problem, but that the metal detector should not be placed over the device.

Baggage x-rays are not you

The belt machine that your bag goes through is an x-ray unit and it is shielded. You do not go through it and you are not standing inside the beam. Your food and your baby's bottle passing through it does not make them radioactive, which is a persistent misconception; x-rays deposit no residue.

The NHS makes the general point about x-rays plainly: an x-ray is a test that takes pictures of the inside of your body using a small amount of radiation, and you should tell the healthcare professional if you are pregnant or might be pregnant. That instruction is about medical imaging, where the beam is deliberately aimed at you, and is a different situation from standing beside a baggage belt.

Asking for the alternative

If you would prefer not to be scanned, the practical points are worth knowing in advance because security queues are not a good place to negotiate.

• Ask before you step into the machine, not after. Once you are in the process it is harder to redirect.
• The private search is a hand search, described by GOV.UK as thorough, and you may be asked to loosen or take off some clothing. It is conducted by an officer of the same sex.
• It takes longer. Build in time if you are going to ask.
• You do not have to justify the request or produce medical evidence.

What to sort out instead

Security is the part of air travel that generates the most anxiety and the least actual risk. The things that matter for flying pregnant are elsewhere.

The NHS advises that flying is not harmful to you or your baby but that you should discuss any health issues or pregnancy complications with your midwife or doctor before you fly, that the chance of going into labour is naturally higher after 37 weeks, or around 32 weeks with twins, and that some airlines will not let you fly towards the end of pregnancy, so you should check the airline's policy.

It also flags the clot risk: long-distance travel of more than four hours carries a small risk of deep vein thrombosis, and advises drinking plenty of water, moving about every 30 minutes or so, and considering graduated compression or support stockings from a pharmacy.

Insurance is the other one. The NHS advises making sure your travel insurance covers pregnancy-related medical care during labour, premature birth, and the cost of changing your return date if you go into labour.

If you have already been scanned

Walking through a body scanner is not an event requiring any action, at any stage of pregnancy, and no follow-up exists because there is nothing to follow up. The dose figures above are the whole story.

That applies equally if you were scanned repeatedly on a multi-leg trip. The exposure does not accumulate into anything meaningful against the background dose of the flights themselves.

The short version

You can be scanned and you can decline in favour of a private hand search, and GOV.UK sets out both. The measured dose from the x-ray type of scanner equals about two minutes of flying, most UK scanners now use radio waves rather than x-rays, and the arch and the wand emit no ionising radiation at all. The parts of flying worth planning for are the airline cut-off date, the clot risk on long flights and the insurance.