London (CNN)Thousands of pregnancy tests have been recalled in the UK after some were found to give false positive results.
False positive results prompt pregnancy test recall
Manufacturer Guangzhou Wondfo Biotech estimated that up to 58,000 affected digital tests with the Clear & Simple brand have been distributed in the UK.
Women who have used the affected tests -- with an expiration date of January 2020 and lot number of DM10220170710E -- have been advised to seek alternative testing.
"It is important people check the lot number of any Clear & Simple Digital Pregnancy Tests they have purchased to see if they have a product from an affected lot," said Duncan McPherson, clinical director of medical devices at the UK's Medicines and Healthcare products Regulatory Agency in a news release.
The manufacturer blamed the "rib height of the test strip brackets" on the tests for causing the false results.
Clear & Simple's UK distributor Healthpoint said: "We are very sorry for any inconvenience and upset that this manufacturing fault may have caused, and we are working closely with the manufacturer to ensure the accuracy of future supplies."