But the health body believes backlogs will be cleared by the end of next month
Manx Care is reporting delays of up to four weeks for non-symptomatic breast screening.
The service was operating at 50 percent staffing earlier in the year, which combined with large monthly patient numbers for August and September, has created a backlog.
Non-symptomatic screening is offered alongside symptomatic clinics.
The health body says residents turning 50-years-old are being invited within three months of their birthday.
Staffing now stands at 75 percent with locum cover.
It's anticipated the backlog will be cleared by the end of October.
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