Patients are waiting almost two weeks longer than they did last year for important ultrasound scans at Calderdale and Huddersfield NHS Foundation Trust, figures show.
The latest NHS England data shows that 725 people were referred for an ultrasound on their pelvis at the trust in June.
On average, those patients had to wait 33 days, from the date of the request to the scan.
This is up from an average 21 day wait in June 2017.
Ultrasound scans are used to detect ovarian cancer, among other illnesses.
Across England, waiting times increased for other ultrasounds, MRI scans on the brain and CT scans on the chest.
Dr Caroline Rubin, vice president for clinical radiology at the Royal College of Radiologists, said trusts were short staffed and under-equipped.
“There are not enough radiographers to do these scans, and equipment is at capacity, so even if we had more staff they wouldn’t have equipment to use,” she explained.
She said the annual data and the RCR’s own yearly census backed up the monthly figures.
“If you look at our data, you can see that the number of CT and MRI scans that are performed has gone up by about 10 per cent each year.”
Research by the college shows one in ten CT scanners and nearly a third of MRI scanners in UK hospitals are technically obsolete, while still being used. On top of this, Dr Rubin says not enough doctors are being trained in radiology and claims more than 10 per cent of consultant radiologist posts are vacant in UK hospitals.