Welcome back to the Forum. I'm pleased for you that your pregnancy continues to progress and understand well that anxiety that accompanies any pregnancy but even more so in the situation of a hard won pregnancy such as yours.  I think you are worrying more than you need to.  Let me address your specific questions:

No.  10 weeks is too far out for the ARS syndrome to occur- this occurs most typi9cally between 2 and 4 weeks and would not occur so late.  Further, when the rash of the ARS occurs, it occurs in combination with other signs and symptoms including a high temperature, severe sore throat and muscle and joint aches.  OTOH, diffuse rashes of the sort you describe, often follicular in nature are common in pregnancy.

No.  We have discussed your ultrasound encounter before, I will not repeat what was said in that exchange other than to remind you that this was a no risk event.  As far as surface exposure to a friend's blood, this too is a no risk event.  First let me point out how unlikely it is on a statistical basis for your friend to be HIV infected.  Secondly, this sort of surface exposure has not been described to lead to infection.  Intact skin is one of our body's most effective mechanism for preventing infection.

Several years ago the guidelines for when HIV testing using 4th generation tests was entirely conclusive changed as the result of a small handful of cases which became positive between weeks 4 and 6 after exposure.  At 4 weeks a 4th generation test would detect well over 99% of recent infections but results would not be definitive until 6 weeks post-exposure.  I should add that if symptoms potentially due to HIV are present and a 4th generation test is negative, then this rules out the possibility that the symptoms are due to HIV.  

Oraquick is a 3rd generation test which only detects HIV antibodies.  These tests are highly reliable any time more than 8 weeks after exposure but despite that, they are our least favorite antibody test as the have a very small false positive rate which is somewhat higher than the false rate for other antibody tests.

I hope this information is helpful and will allow you to move forward without continuing concern.  EWH

1) It is possible that this rash has been present longer than one month. As I mentioned, the bumps are so small and I only noticed them after I saw one with a pustule.  Then I started watching for them. For arguments sake, if these bumps have been present for much longer, would that change your assumption? 

2) I realize there are ARS-related rashes and there are rashes that tend to be more pronounced with a immunocompromised person. When I've read about Molluscum Contagiosum, for example, the internet essentially says disseminated Molluscum can be a sign of HIV infection. Assuming again for arguments sake these are molluscum, would you be concerned that I have them widespread? Could pregnancy cause enough of an immune suppression that it would be more likely for molluscum to be widespread and on areas of the body in no way associated with the groin (note: no lesions are preset on my genitals)? 

3) If these were molluscum, I would need to ask myself how I got them. I hate to even think of this, but would I need to be concerned about infidelity from my husband?

4) The reason I am so concerned about Molluscum is that I had them before in my 20s (diagnosed and treated by OBGYN). These look similar. I thought most people had immunity once they have been previously infected, hence why I am concerned with the status of my immune system. 

Thanks again! 

Straight to your f/u questions:

1.  If anything, if the rash has been present longer than a month it makes it even less likely that it re[resents HIV or any other STI.

2.  I think the first part of responding to this question is to determine if your dealing with molluscum or not.  Your family doctor has indicated that the rash he/she has examined is not molluscum.  If you need a second opinion on this, I'd strongly advise you to do so BEFORE you go down the "what if" trail.  What you describe does not really sound like molluscum and while pregnancy may be somewhat immunosuppressive, I have never heard of pregnancy-related disseminated molluscum.  

3.  See my comment above regarding "what ifs".  Most molluscum however is not sexually transmitted.  The infection is primarily a disease of childhood.

4.  Understood- see above

As I read these comments, I find myself wondering if you have been on the internet.  I hope not- the internet is NOT the friend of anxious persons.  All too much of what is there is taken out of context, out of date, overstated or just plain wrong.  EWH

I just tested negative with the Oraquick saliva test 11 weeks and 1 day post incident (where I had blood contact). May I accept these results as conclusive? Thank you and I realize your response will conclude our thread.