Researchers say menstrual blood testing could offer a simple alternative to cervical screening.
A sanitary pad fitted with a blood strip can detect HPV, which causes most cervical cancers.
Women could use the test at home without a clinical examination.
A large study in China compared menstrual blood samples with clinician-collected cervical samples.
Researchers studied more than 3,000 women with regular menstrual cycles.
They published the findings in BMJ.
The pad-based test detected serious cervical cell changes with similar accuracy to clinical sampling.
It showed a sensitivity of 94.7% for detecting high-risk abnormalities.
Researchers said the method could improve screening access for non-attenders.
Cancer Research UK welcomed the findings but urged further trials.
Experts stressed the test remains experimental and may not suit everyone.
Eve Appeal said offering more screening choices could save lives.
