This scan is performed in the range of 6-18 weeks and is used to confirm the viability of the pregnancy i.e. to check baby's heart beat and check that the baby is in the uterus. This can be performed from approximately 6 weeks onwards or after the fetal pole/s is 7mm long in which fetal cardiac activity should be demonstrated.

Gross abnormalities may be detected at this stage but an in-depth anatomy check is carried out at the Anomaly scan at 18-24 weeks (see below).  During this scan a measurement of the baby is taken from its head to bottom (crown to rump up to 14 weeks) to establish the gestational age of the baby. After 14 weeks this is calculated by head measurements, thus calculating the expected date of delivery.

Additionally, it is used to determine the number of babies along with their gestational age. It may be necessary on occasions to perform an internal trans-vaginal scan to give a clearer image. 2D Image supplied as black and white photographs.