A positive "Stallwohy&;s sign" is suggestive of which of the following conditions:
Twin pregnancy
Breech presentation
Vesicular mole
Low lying placenta
If the earlier scan showed placenta completely over the internal os it is most likely to persist in the later scans.If the 18 -20 weeks scan revealed a low lying placenta or marginal placenta prae,placental localization is best repeated around 32 weeks (refer pgno:130 sheila textbook of obstetrics 2 nd edition)
General obstetrics