One in four women didn't have a pap smear test in over three years, despite expert recommendations to do so.

YouTuber Zoe Sugg, aka Zoella, pictured above, recently filmed herself getting a pap smear in an effort to encourage other women to do the same.

A pap smear test checks whether the cervix (the opening to the womb from the vagina) is healthy. It tests for pre-cancerous and abnormal cells, which if left untreated, can lead to cervical cancer.