Imperforate

Only prepubertal girls have a noticeable hymen; the hormones of puberty causes it to basically dissolve except in rare cases of birth defect called imperforate hymen.

Apparently, the teenager has what the doctor calls an “imperforate hymen, and needs the hymen to be broken so that the teenager could commence her menstrual period which appears to have been stalled by a lack of passage for blood to flow through.

In rare cases where imperforate hymen does not resolve itself prior to the first menstrual cycle and goes undetected, blood and endometrium are trapped within the uterus of the woman until such time as the problem is resolved by surgical incision.

It was produced without perforations (imperforate) and consequently had to be cut from the sheet with scissors in order to be used.