U dont always see it! Ive had 3 baby's & only visibly lost my mucus plug with my 3rd! I had to google as I wasn't sure if it was my mucus plug or if it was the evening primrose I had been using vaginally lol google pic's were grose lol but they r useful :-)
N also because ready for early labor at times. Good luck
It's the mucus that's in between your cervix and the baby to help keep germs from getting to the baby, Google to see what it looks like