Difference between Blighted Ovum and no pregnancy?

  Hello -
  I had two faintly positive HPT's at 12 and 14dpo. I started lightly bleeding at 5 1/2 wks.  When I had a transvaginal ultrasound - she could detect no signs of pregnancy. Would'nt I have some detection (tissue etc.) if this was a blighted Ovum?  My temperatures  indicated that I was pregnant, so I'm confused why even a sak was not detected? I have since started to bleed heavily. When can I resume trying to Concieve (conceive)?
  Thank You AZG1

[hfhsmdrcs]

_
Dear AZGI:
A chemical pregnancy is one in which the pregnancy test is positive and nothing is recognized by ultrasonography. A clinical pregnancy is one that is recognized by ultrasonography.
It takes time for the early cells that produce enough hCG to give a positive pregnancy test to divide and grow to a size that the current ultrasound technology can image the gestation.
Following this bleeding, use barrier contraception until you have a normal menstrual period (4 to 8 weeks, average 6 weeks). Resume attempts to conceive.
Keywords: chemical pregnancy.
This information is provided for education purposes and is not a clinical consultation. If you have specific questions, please speak with your healthcare provider.