What Causes Absence Of Foetal Cardiac Pulsation During Pregnancy?

Sir, yesterday we did obstetric sonography which shows that foetal cardiac pulsation are absent. Sir do u think is there any hopes. She dont bleed or not any problem right now.please guide for further. Also want to know what is the reason for this. at the time of 5 week 5 days cardiac activity was positive but now at 9 week it showing absent.My wife was diagnosed with bicornuate uterus.This was first pregnancy after 7 yr of marriage. Can she again conceive naturally? Please help us doctor