Researchers say testing menstrual blood could provide a simple alternative to cervical screening.
A sanitary pad fitted with a blood strip can detect human papillomavirus, which causes most cervical cancers.
Scientists in China compared pad-collected menstrual blood with clinician-taken cervical samples.
The study involved more than 3,000 women aged 20 to 54 with regular periods.
Results, published in BMJ, showed similar accuracy between both methods.
The pad test detected serious cervical cell changes with 94.7% sensitivity.
Researchers said the method could offer a non-invasive, home-based screening option.
It may help reach women who currently skip clinical screening appointments.
Cancer Research UK welcomed the findings but urged further trials.
The Eve Appeal said choice in screening methods could save lives.
Experts stressed the approach remains experimental and may not suit everyone.
