I'm 34 weeks and had some minor spotting last night (stopped almost immediately). Midwife examined me and is "99% sure" that it's nothing serious, but is recommending an ultrasound to check for placenta previa, just in case. We're planning a homebirth, and have declined ultrasounds so far.
My general understanding was that complete previa would just about always cause heavy, painless bleeding either late in the 3rd trimester or in early labor... but now I'm not sure that's the case. I've ran into a few mentions of "asymptomatic previa", but I can't find any research on the rates/likelihood of that. Any ideas?
We'd prefer not to do the ultrasound now if the risk is infintesimal (we're under 10 min from the hospital), but I also don't want to take a significant, unnecessary risk.