What happens during a mammogram?

Sue Oliver Sue Oliver Professional Head of Mammography & Laser Safety
Having a mammogram doesn't have to be a daunting experience. Nuffield Health's Professional Head of Mammography and Laser Safety, Sue Oliver, walks us through the exam.

Most women, and some men, will have not just one mammogram but many. Over time, people get more comfortable with breast screening, but your first one may invoke embarrassment, anxiety or even fear. Like so many medical investigations, mammography pushes the boundaries of what many people are comfortable with. But the reality is likely to be far less confronting than you might imagine.

The partial nudity

You will have to allow your breasts to be seen and even handled by a relative stranger. Take comfort from the fact that your mammographer is a professional, here to help and always female.

Undressing to the waist is an essential step to getting a clear scan. Any material other than breast tissue in the scan would obscure details and render the image useless.The mammographer will help position your breast correctly on the plate. This is essential to get the best quality image to help diagnose any issues.

The radiation exposure

Mammograms use X-rays to take detailed images of the breast tissue. This exposes the patient to a very low dose of radiation. Every exposure to radiation comes with a small risk, but it is much lower than the risk of not having the exam. In a mammogram, the dose is roughly equal to the amount you'd be exposed to on a return flight from the UK to Australia - a journey many happily take with little concern about radiation.

The compression

To get a clear scan, each breast needs to be held in place between two plates. The grip needs to be firm so there is no blurring of the image through movement. It may be uncomfortable and very rarely it may be painful. If you do experience discomfort or pain, tell your mammographer right away and they'll do what they can to make you more comfortable.

Each breast needs to be scanned twice, once from top to bottom and again from side to side. Each scan takes about one minute. Once the scan is taken, the compression will automatically release and you'll be free to move away from the machine.

The results

Most women who come for a screening don't have cancer. Around 96 in every 100 women tested will get a normal result. About four women will require extra tests but three of them will be given the all clear. So chances are, even if something is discovered in the exam, it's not breast cancer after all.

Being aware of your own breasts and self-checking regularly is still the best defence against breast cancer. It can be a shock to discover a lump and it's natural for your mind to turn immediately to cancer. Any discovery should prompt a visit to your GP, but jumping to conclusions will only cause unnecessary concern.

Last updated Tuesday 27 October 2020

First published on Thursday 14 January 2016