Placenta - anterior in upper and lower uterine segment, edge of placenta is 28 mm away from internal os, what does this mean?

Normal: The placenta is along the anterior - front- wall of the uterus and over 1 inch from the cervix. This is a normal location.

Not a placenta previ: this phrase describes the location of the placenta,including the relationship to the cervix. The usual advice would be that it's safe to attempt a vaginal delivery if the edge of the placenta is at least 20 mm from the cervix.

It means all good!: The placenta is far enough away from the internal "hole" of the cervix that previa--a dangerous condition that can cause hemorrhage--is not an issue. The placenta has to go somewhere--the front (anterior), the top (fundus) or back (posterior). I don't know any more about your condition but based on that info, it all sounds ok!

You should be fine: When the placenta covers the internal os we call that situation a placenta previa(it literally means the placenta is presenting before the babies head or buttocks).A placenta in the location described as 28mm away from the os is considered a low lying placenta and does not carry the same risk of bleeding as a previa.Depending upon what trimester of pregnancy it is discovered it may dissapear