The National Screening Service is urging women who receive BreastCheck appointments to carefully check which centre they are being called to.
Since last week, a number of women have been arriving at the wrong centre.
Since last week, BreastCheck been screening in two locations in the county – Letterkenny and Donegal Town.
However, they say some women who were invited to screening in the Donegal Town mobile unit have been arriving for screening at the Letterkenny mobile.
The temporary Donegal Town unit arrived last week, and will stay for the next number of weeks.
BreastCheck are asking women to carefully check their appointment letters, so that they know whether they should go to Letterkenny or Donegal Town.
In some cases, it will not be the same centre that previous tests were held at.
BreastCheck say if people attend the wrong unit, they may not be able to offer a test.
If anyone has any questions they can contact the BreastCheck Western unit on 091 580 600 or Freephone 1800 45 45 55.
