Welcome to HCM.
Your wife is carrying 14wks post c/s pregnancy
USG scan reveals SLF with low lying placenta. All things are within normal except low lying placenta.
Actually low lying placenta is not much significant in mid pregnancy or in 2nd trimester.Also placenta just reaches up to os and not fully cover.It is more significant on 3rd trimester.
You need to repeat the USG scan around 28-32wks to observe the location of placenta.
Risk of developing APH or Placenta previa
is mild to moderate in your case as Post c/s is always a risk factor. So you should concern about that.
Also you should to be known about complication of placenta previa like separation of placenta, early bleeding,IUGR
etc. So need additional monitoring to your wife and always consult to your doctor.
Avoid heavy work and long journey.