NORMAL 4 - 5 WEEK PREGNANCY
At around 4+2/40 a gestation sac becomes visible transvaginally, measuring 2mm.
It grows 1mm per day and very soon a yolk sac can be seen within the gestation sac. By around 5+5/40 a tiny fetal pole can be seen and this is around the stage a fetal heart first becomes detectable.
This transvaginal ultrasound demontrates the uterus in longitudinal section.
As the operator fans from one side to the other the myometrium is clearly distinct from the more echogenic endometrium.
A small gestational sac is seen buried within the endometrium. Within it a tiny yolk sac is seen, but it is too early in this case to see a fetal pole or heart beat.
This is a normal very early pregnancy.