It initially appears as a round, anechoic structure.
In experienced hands, it may be detected as early as 30 days gestation by TVU.
One gestational sac seen with 2 yolk sacs visible inside it Identical (monozygotic) twins.
This results from an early embryo dividing into 2 genetically identical embryos.
The embryonic pole appears adjacent to the yolk sac, soon showing cardiac activity.
Since the connecting stalk is short, the embryonic pole is found near the wall.
While your sonographer takes measurments they will explain what you are looking at.
It may not be easy for you to make out what you are seeing on the screen in the early scans.
If cardiac activity can be detected but the embryo is not measurable, the GA is about 5.5 to 6.0 weeks.
It is recommended that all pregnant women have a scan in the first trimester, to establish the date when the baby is due, check the number of babies also the position of the placenta.
First trimester ultrasonic scans may show 'soft' markers for chromosomal abnormalities, such as the absence of fetal nasal bone or an increased fetal nuchal translucency (back of the neck) to enable detection of Down syndrome fetuses.
It's like 2 tests in 1 - it first detects if the pregnancy hormone is present with over 99% accuracy from the day of your expected period, and if you are pregnant, it ALSO indicates how many weeks since conception occurred 1-2, 2-3 or more than 3 weeks (3 ).
The Weeks Indicator is 93% accurate in detecting when you conceived.