Sonography will confirm that pregnancy has reached inside the uterus.(rules out ectopic pregnancy). We can also get an idea about number of fetuses (eg.Twins)
It is a sonography test offered at 11 to 14 weeks of pregnancy to check
a) Growth and development in first three months
b) Uterine artery PI(For early prediction of pregnancy induced Hypertension/BP)
c) It also tells you about the probability of your baby having genetic abnormality( especially chromosomes number 13,18,21) It is not a definitive test but only categorises you as Low Risk or High Risk.
When combined with a blood test called Double Markers, the accuracy of the categorization increases to 90% to 95%
If combined results of these two tests come as high risk then Amniocentesis is advised for confirmation.