Almost 40,000 women in Warwickshire did not attend their last smear test, NHS figures show.
The take-up rate for cervical screenings in the county has fallen for the fourth consecutive year.
Only 73.2% of the 148,300 women who were due a smear test before the end of March attended an appointment.
This means around 39,720 women missed out on the ‘life-saving’ programme.
Cancer charities have said the “plummeting” attendance rate in England is enormously worrying.
Attendance across England has also fallen for the fourth year in a row, reaching 71.4% last year.
Robert Music, chief executive of Jo’s Cervical Cancer Trust, said women are finding it increasingly difficult to access appointments.
He said: “These statistics are highly frustrating and, coupled with rising cervical cancer diagnoses, an enormous worry.
“Women in England are frankly being let down.
“Many struggle to get screening appointments at their GP, access through sexual health is declining, and there is limited provision for those requiring extra support including survivors of sexual violence or those with a learning disability.
“We cannot sit back and let cervical screening coverage continue to plummet or diagnoses of this often preventable cancer will rise and more mothers, daughters, sisters and friends will be lost.”
Cervical screening is a test that looks for changes in the cells of the cervix which could develop into cancer.
Women aged between 25 and 49 are invited for a screening every three years, while those aged 50 to 64 attend every five years.
If they do not have a test within six months of their latest invitation they are counted as not having attended.
In Warwickshire, the younger age group were significantly less likely to be up to date with their tests.