I live in Switzerland and recently made a two-week whilstle stop tour around the UK with my 4 year old son during his half term holiday involving 6 flights. I was 33 weeks pregnant at the time - it was very visible! To my surprise when travelling through London City Airport (my second flight) I was politely tapped on the arm when going through security screening and was told "you must not pass through the security machine".

I went through a gate instead and had a brief body search. At my next airport (Manchester) I queried the safety of passing through screening (I had always assumed it was safe as there are no notices to the contrary) and was told that different airports have different power machines and at London City, they must consider it unsafe.

That got me worried. I have travelled frequently throughout both my pregnancies and often at a stage when the pregnancy is not so visible but conversely the foetus is far more vulnerable. Can you confirm whether these machines are safe or not? Thank you Elizabeth-Claire Bazin, Seltisberg Switzerland

Family travel writer Jane Owen replies: wow – that’s quite a schedule with a four year old and a bump. I put your concerns to London City Airport and received this reply from Strategy Director Charles Buchanan: "On consulting our security manager she has told me that our metal detectors and X-ray machines are no more powerful than others installed at airports, and are regularly checked to ensure that they are operating properly.

"We do however recognize that some passengers, particularly pregnant women and those with pacemakers, have some concern about passing through the archways, and our staff are trained to offer these passengers the alternative, if they choose, to be hand searched. This service is simply a reassurance for our passengers and an example of the personal service we extend to all who use London City Airport."

I also spoke to BAA - which owns Heathrow, Gatwick, Stansted, Manchester Southampton, Edinburgh, Glasgow and Aberdeen airports - and its spokesman was adamant that none of the security equipment used in its airports, from metal-detecting arches to hand-held gizmos, is in any way harmful to an unborn child.

He added that a new machine in Heathrow’s Terminal 4 uses low radiation (low enough, according to manufacturers, that you’d get more radiation standing in the sun) and gives pregnant women the option of an alternative, no-radiation security search.

The other issue to think about if you plan to fly during pregnancy is that some carriers will not carry certain pregnant women.

It's usually to do with multiple foetus pregnancies and/or being heavily pregnant. Some airlines ask pregnant women to carry a note from their doctor or midwife. The golden rule is to check the rules before you buy your ticket.

Got a question about family travel? Email our trio of experts at yoursay@timesonline.co.uk - Chloe Bryan-Brown takes care of questions for the 0-6 year olds, Emma Mahony handles the 7-12 age group and Jane Owen writes about teenage and single parent travel.

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