6 weeks dating
The developing arms and legs become visible as small swellings (limb buds).
Little dimples on the side of the head will become the ears, and there are thickenings where the eyes will be.
Ultrasounds show the blood flow, which is another important clue in establishing the exact location of your pregnancy and if you will be able to carry the pregnancy to full term.
The fetal pole is visible at the 6 week ultrasound – this is the shape of the embryo, which is going to develop into your baby.
[Read more about Miscarriage] Chorionic sac and yolk sac are two other features which are checked at the first ultrasound.
The chorionic sac is the fluid cavity which holds the fetus for the entire pregnancy, while the yolk sac is the source of nutrition for the embryo before the placenta is fully developed and is found inside the chorionic sac, which is called gestational sac.
During this second ultrasound, the doctor can evaluate the changes which took place and see if the embryo is growing as expected.
If you are having a 6 weeks ultrasound the doctor will probably choose to use a vaginal ultrasound machine, which consists of the insertion of a long wand into your vagina.First, the location of the pregnancy will be visible at the first scan.The test can easily show where the pregnancy is located, which is very important for the future: in the case of an ectopic pregnancy, when the embryo is placed outside the uterus, in the Fallopian tube, the doctor will be able to advise you on what’s best to do next.By the time you're 6 to 7 weeks pregnant, there's a large bulge where the heart is and a bump at the head end of the neural tube. The embryo is curved and has a tail, and looks a bit like a small tadpole.The heart can sometimes be seen beating on a vaginal ultrasound scan at this stage.