Cervix: The OS
The os is the little opening in the middle of your cervix (side note: the cervix is made of cartilage like the tip of your nose). Depending on whether you have had kids or not the os may slightly change in appearance: appearing more like a slit once you’ve had kids.
The os allows menstrual blood to flow out of your uterus and into your vagina. The os will open a little more during menstruation and close a little afterwards, until it opens up again during ovulation. Yup, it also allows sperm to pass through. During pregnancy, the os will close upon itself to help protect the fetus and at the time of birth it is the os that will dilate to ten centimeters to create enough space for a baby to pass through.
It has come to my attention that a lot of people will search the Internet for information on inserting penises or other stick like objects into the cervix. DO NOT under any circumstance try to insert anything into the os. I mean it, don’t do it. I’m not just saying this because it will be painful, it will be, but I know that’s not exactly a deterrent for everyone. I say this, because it is extremely bad for your health. To quote Scarleteen “There’s a lot of reasons women who have had to have backalley abortions have died, gotten very ill or become infertile, and some of the any is because of inserting things into the cervix without medically sanitary conditions.”
Seriously, unless you are having an IUD installed or you midwife/doctor is checking to see just how dilated you are, STAY AWAY FOR THE OS (you can touch it with clean hands, just don’t insert anything into it). Not all holes are meant to be penetrated.