植入性胎盘

okay ladies I'm gonna ask you to recall it's probably a really painful memory and guys use your best imagination with this one you know when you're wearing fake nails they're glued on really well to your actual nail and when it comes time to remove them you're supposed to soak them in some solution that dissolves the glue but when you're super impatient sometimes you rip the nail off and sometimes your actual nail very tragically comes off with a fake nail and what's left is a nail bed that's bleeding profusely because the nail bed is a really vascular place it has lots of blood vessels running through it so with that picture sort of in the back of your head let's talk about the placenta so you have the uterus before there's any embryo and the wall of the uterus is made up of three layers on the inside there's the endometrium the endo endo and no metrium all the way on the inside and then the myometrium that's my oh my oh my Oh meaning muscle because this layer is composed mostly of smooth muscle myometrium or the muscular layer in the middle and that leaves the peri metrium peri peri fur for periphery on the periphery of the uterus peri metrium all the way on the outside of the wall and it's the endometrium that's all the way on the inside that changes that actually changes to prepare for the implantation of the embryo and that process of change that the endometrium undergoes is called decidua lies ation it's a process where where blood vessels grow profusely and glands in the endometrium become filled with nutrients like glycogen and at the end of this process at the end of the decidua zation the endometrium is called the decidua so it goes from being called the endometrium to being called the decidua now looking at the embryo side of things that outside of the embryo has these cells the cells are called trophoblast travel bus that's what I'm putting in green over here those cells called trophoblast and these trophoblasts actually interact with the decidua they're actually responsible for the embryo implanting into or burrowing into the decidua to eventually form the placenta now the reason why I'm going into such a detail about this process about how the trophoblast dig into the decidua which by the way the part of the decidua that the trophoblast interact with is called the decidua basalis that's a specific name it's called the decidua basalis the reason why I'm going into detail about this is because of a set of disorders called placenta accreta in Krita and / crea I know it sounds like the name of Cinderella's evil stepsisters so in these disorders the placenta is too firmly attached to the uterus so instead of the placenta attaching to the decidua basalis or attaching just to the decidua basalis it attaches too deeply to the myometrium and that's usually because the decidua basalis is defective it's not thick enough and the trophoblast needs more to grab on to so they have to dig deeper into the myometrium and before I go into what causes a defective decidua let's tease apart the three evil stepsisters so placenta accreta is when the placenta attaches to the myometrium so it kind of attaches through the decidua basalis and attaches onto the myometrium and that's called placenta accreta on Korea right now placenta accreta is when the placenta actually penetrates into the myometrium so it goes all the way through and really digs deeply into the Maya metrium and that's called placenta in Krita and finally placenta percreta is when the placenta digs all the way through the myometrium and the peri medium and sometimes we'll we'll even invade into the adjacent bladder wall and and going all the way through those layers is called placenta percreta all right so why does this happen how do you get a defective decidua basalis a lot of times as a result of some prior surgery in the uterus so for example a history of a c-section on a history of a uterine curettage you curettage which is a type of procedure in which the lining of the uterus is scraped away for for a variety of different reasons or a myomectomy a myomectomy which is another type of procedure that's used for the removal of fibroids in the uterus so any one of these procedures can lead to a thin or scarred endometrium that doesn't form a juicy healthy decidua another things that another thing that can sometimes happen is that the placenta implants in a lower segment of the uterus rather than at the top like it's supposed to which is a condition that's called placenta it's called placenta previa and the problem is that the lower parts of the uterus generally have thinner walls and they don't form as thick of a decidua so these are a few of the things that can lead to a defective or a thin and an inadequate decidua and these risk factors are pretty significant so much so that if a woman has had three or more c-sections in the past and she has a placenta previa she has a 50% chance or one in two chance of having a placenta accreta so that's a type of situation in which you would probably be on the lookout for a placenta accreta so you might want to do some imaging on the uterus such as an ultrasound or an MRI because that becomes important in these cases now I also want to mention that there's some thought that sometimes you can just have trophoblasts that are too aggressive in their implantation or in their digging and that can contribute to the formation of this disease okay so a lot of times the way that the placenta accreta is discovered is at the time of delivery when it's found that the placenta is really hard to remove and when the practitioner sort of inserts their hand to manually extract the placenta they find that it's really firmly attached to the uterus or someone might pull too hard Leon the umbilical cord trying to pull the placenta out and that rips apart the placenta from the uterus and leads to a lot of bleeding kind of like when you rip away a fake nail like we were talking about earlier and really because of that because of that risk eating the best way to manage this disorder is with a hysterectomy or a removal of the uterus right after the baby's delivered and I know that sounds a bit dramatic you might say well why can't we just remove the placenta carefully bit by bit or leave it in there to come out on its own and the answer is that trying to remove it even very carefully puts the mom at risk for hemorrhage and even death and leaving the placenta intact places a significant risk for infection so really the only option is hysterectomy only very very rarely in a very young woman who expresses a very strong desire to have children in the future perhaps then an approach to conserve the uterus can be undertaken if only there were a glue dissolver sorts that could allow the placenta to gently peel away from the uterus then then perhaps in the future you may have a way to avoid hysterectomies but unfortunately not for now so all in all those are some details about placenta accreta in crete ax and percreta