[monkaha]

I was told at my appt today that the nonstress tests (NSTs) that they want me to be doing must be done twice each week because they are only predictive for 3-4 days. (I'm considered high-risk because of Lupus, if that makes any difference in the search/starting point)

Does anyone have any links to research that prove/disprove that? I was of the impression that NST's could tell you what was going on right then, but don't see how they would predict future problems. I was also given the option of weekly biophysical profiles (BPP), which they said would predict placental health for closer to a week. Again, this doesn't make any sense to me.

Hoping someone can point me towards some research (even just get me started on my own with some good sites for birthing/preggo data). Thanks!

 

[DoomaYula]

Huh. I don't have any scientific evidence, but I had a lot of NST/BPP with my twin pregnancy, and it seemed only to hold true for when I was having it done. When I had them on Friday afternoons, the doc always told me to come in over the weekend if I was having any pain or anything like that. I don't know, but that does sound strange.

 

[rebirth]

It sounds strange and in oppositio to what I know about NST too.... But I don't have any links at the mo. I'll look if no one else has.

 

[soxthecatrules]

I was given somewhat similar advice regarding NSTs. It will be interesting to see what we come up with. I'll do some looking later tonight. Had 8 weeks of NSTs w/DS and 5 weeks of them w/DD. My risk factors were gestational diabetes and my really big issue was chronic hypertension w/pre-eclampsia on top of it. I know with PE the baby can start having problems real fast so I was under the impression that was why they wanted the tests so often (2x weekly).

All I can say about my NSTs is w/DS they were done at the hospital in L&D and took forever as in 3 hours was the average!!! The ones w/DD were done at my OBs clinic and never lasted more than 20 minutes. Of course, DD was way more active so I don't know if it was just a difference in children or the nurses administering the tests. DS ended up being 4 weeks early because of PE. Others on this board may disagree w/me but I firmly believe that if I had not been monitored so closely that we probably would have lost him.

 

[squishymama]

The way I learned it was that a reactive NST is reassuring for 72 hours after it is done. NSTs can only predict placental insufficiency so that is why providers will still counsel you to call if there is a change in your baby's activity level. Cord accidents are entirely unpredictable. I thought a BPP was also 72 hours.

 

[maxmama]

Took only a quick look, but PubMed didn't have anything that jumped out at me. I'll look at Cochrane later.

It makes sense that NSTs are predictive of adequate oxygenation for some period of time (though I suspect the 72 hours thing was pulled out of someone's ass and has since become standard of care), since along with immediate problems (decels) they also look at long-term issues of placental sufficiency (variability), which is much more predicitve of fetal hypoxia and also much less dramatic in onset.

Incidentally, I found a smallish study (n=230) looking at diurnal patterns of NST reactivity, and they found that scheduling NSTs at night reduced the number of nonreactive NSTs requiring BPP or mBPP by 50%.