Undiagnosed placenta previa?

Published

I have a question for you experienced nurses:

Does it make sense that a woman would not be diagnosed with previa until they showed up at full term in labor bleeding profusely? I just had never heard of this happening before and don't understand why it wouldn't have been seen on u/s.

Shannon

Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

http://www.nlm.nih.gov/medlineplus/ency/article/000900.htm

excellent link to an article about placenta previa. Has graphics, too.

Up Vote Up Vote ×
I have not heard of a placenta migrating "downward"......

it really defies physics/physiology, if you think about it.

It implants thru the villi network very early in gestation. As the uterus grows, it "pulls" the placenta away from the cervical os upward---the placenta firmly attached to the uterus by this time.

To migrate down (if possible) would be a bad thing...it would have to have detached to do so.

Exactly, SBE, that is what I was thinking originally. So, then whoever did the 20 week u/s missed it, right? And isn't that a pretty big thing to miss? Is there a reasonable explanation as to why it wouldn't have been seen then?

Up Vote Up Vote ×
Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

Well I just read that somewhere over 95% of previas are actually MIS-diagnosed (meaning they are not previa at all).

So what can we take away? Well, u/s is far from an exact science and the accuracy of results rest in the hands of the experience of technicians and those making the intepretations.

I would "think" a low-lying placenta, once diagnosed/noted would require an inherent follow-up!

Up Vote Up Vote ×
Specializes in Education, FP, LNC, Forensics, ED, OB.
OK, so here is my question--it is possible then, that at 20 weeks it wouldn't have been a previa, but later on the placenta can move down? I had never heard of that, only thought it would sometimes move up! Great, something else to worry about if I am ever crazy enough to try for a 3rd, LOL!

Not exactly. A praevia (low-lying) on an earlier US could be found and as the pregnancy progresses.....the uterus grows up and out and the placenta with it. In fact, a low lying placenta can be a common finding in some women very early on. No, at 20 weeks, the placenta, if low-lying MUST be evaluated, followed and another US later. No, the placenta does not move/migrate down.

Sorry for any confusion with my previous statement.

Up Vote Up Vote ×

Talked to my friend today. She had a level II u/s at 20 weeks. I just don't get how they missed it. I am so thankful that the outcome was good.

Shannon

Up Vote Up Vote ×
Specializes in Education, FP, LNC, Forensics, ED, OB.
Talked to my friend today. She had a level II u/s at 20 weeks. I just don't get how they missed it. I am so thankful that the outcome was good.

Shannon

I am a little dumbfounded. Hmmmmm.........

Up Vote Up Vote ×
Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

A level II eh?

wow that is wrong.

Up Vote Up Vote ×
A level II eh?

wow that is wrong.

Yes, she is over 35 and refused pre-natal testing so they did a level II.

Up Vote Up Vote ×
Specializes in Case Mgmt; Mat/Child, Critical Care.
Yes, she is over 35 and refused pre-natal testing so they did a level II.

Wow, that is weird....sounds more like an abruption than a previa....just is too bizarre that they would not document the placenta on a level II ultrasound.... :confused:

Up Vote Up Vote ×
Wow, that is weird....sounds more like an abruption than a previa....just is too bizarre that they would not document the placenta on a level II ultrasound.... :confused:

OK, this is the latest thing she told me...because I said, "Are you *sure* it wasn't an abruption?" and she said the doc told her that yes it was an abruption caused by previa...does this make sense?

Up Vote Up Vote ×
+ Join the Discussion