The inspiration for this one came from a pub conversation. It’s time for…
The hymen is a often described as a ‘membrane’. It is membranous tissue, but this can lead to some confusion-
This is called an ‘imperforate hymen’. The main reason it needs treatment (i.e. surgical removal) is that it means that menstral blood cannot drain during a period.
So, as with many aspects of genitals, individuals can be VERY different and this is completely normal.
References (a note):
When I have an idea for something, I usually start by looking at some standard Gynae textbooks and then try to find reliable looking online sources (e.g. NHS, clinical guidelines). They failed me somewhat on this topic. I’ve found a teeny tiny amount of information from my textbooks (mainly on imperforate hymen). This is basically a way of explaining why my main source is a wiki page (here)!