Define this for me?

[JamieCatheryn]

I was reading some birth stories again today and realized I really don't know what skid marks are. Obviously you can get them as minor trauma to the opening somehow, often instead of tearing. But what are they exactly? I looked it up but couldn't find anything.

[Hayes]

think of them as stretch marks on your labia or around your vagina. You don't tear, you just stretch a bit further than normal.

[tinyshoes]

Skin can stretch.

Skin can stretch a whole lot without breaking....

...but...

...when skin stretches so much that the top layers of skin are "broken," and if it's in your crotch region, it's a skid mark.

The nickname is a joke based on the speed at which the baby has exited the birth canal; like a race car dashing off from the starting line, baby's speedy exit left a skid mark. The idea is, if a baby leaves mom slowly, there will be ample time for skin to stretch and not be broken. Of course, even slow crowning events can result in a skid mark.

Another way to imagine a skid mark is to think about when your face/hands are chapped and the top layer of skin has been damaged by cold/wind. That is kinda like a skidmark. It can burn or hurt if chaffed, or when you wet your hands, just like a skid mark on the labia will sting when you pee...and like a chapped face, it will heal quickly.

When skin stretches so much that skid marks occur, it can stretch so much that it breaks. Then you have a tear--the skin layer is completely broken open, like when you skin your knee on pavement. On your post-partum crotch, this type of tear is called a 1st degree tear (or laceration.)

When your skin stretches so much that it breaks and is a tear, the underlying muscle could also tear: then you have a true tear, a 2nd degree tear (or laceration.)

Every episiotomy is always a 2nd degree injury involving muscle. The birth attendant decides where the injury will go. As evidenced above, there are two kinds of tears that are less traumatic than an episiotomy, further, the woman's body decides where those tears will happen. This is why the Earthy-birthy crowd's creed is, "it's better to tear than have an episiotomy."

When skin stretches so much that is breaks and tears and the underlying muscle tears and the injury continues towards the anal sphincter, it is a 3rd degree tear (or laceration.) If the injury continues through the anal sphincter, it is a 4th degree tear (or laceration.) 3rd and 4th degree tears are most commonly the result of an episiotomy that extended into the anal sphincter tissues. And by extend, I mean, the care practicioner cut a regular episiotomy but that cut caused the skin to continue tearing on its own.

3rd and 4th degree injuries require skilled suturing and repair for optimal results.

It is my understanding that unless muscle is involved, stiches to repair birth injuries are optional. This means that skid marks and tears might not be sutured at all--it often depends on the attitude and opinions of the care provider. At my home birth, for example, where I was attended by two midwives, one felt my tear needed a stitch, the other felt that no stitching was the best choice.

HTH