What effect does the menstrual cycle have to HIV tests?

[HistoricDuck]

I am unsure of which testing method is being used for my tests (blood draws sent to lab, not that those details narrow it down much, sorry), but before each appointment they made sure I was not currently menstruating, saying something like, "It can effect the test". Every time I've gone in I meant to ask for clarification but I wound up being as brief as possible considering the recent events making healthcare a very busy setting. If anyone here can give me a rundown on why a person should avoid HIV testing during menstruation, I'd appreciate it.

[CurfewX]

There does not appear to be any scientific evidence for the claim that menstrual cycle would affect HIV testing.  

[HistoricDuck]

I certainly couldn't dig anything up. I suppose I'll have to cave in at my last visit and ask what on earth they are on about. Thank you so much for the reply.

[AnxiousNoMore]

What was your risk and when did it happen? How often do you decide to test?

[HistoricDuck]

Multiple instances of penetrative vaginal intercourse with someone known HIV positive, no condom. I contacted my local CDC department and was refered to a clinic where we discussed my exposure events and in the end I'll have three tests total.

The first test was a little over a month post exposure, another at three months post exposure, and my last is set at 6 months.  This has been my only experience with unsafe sex, so I've been deferring to the clinic and complying with what they ask of me.

[AnxiousNoMore]

You only need to test conclusively once, so now that you know that, it will be abnormal to do any more tests. Any test is conclusive after 3 months.

[HistoricDuck]

I understand the abnormality of it, but as I said previously I deferred to the clinic in matters of testing as I trust their judgment over my own. This has been my only experience with any kind of STI/D.

When I first went in I had only looked into what information they were likely to ask of me and what I should expect out of my first visit. I am anxiety prone so I didn't want to give my mind any fuel via googling details.

I only realized the third test was out of place when I started trying to figure out what the whole menstruation thing is about after my final appointment was set and I became informed of testing procedure.

At this point I've been staring at the "finish line" of six months for so long I don't think my mental state would be content without it. I assumed for months the clinic made that choice for good reason so that final test has some weight in my brain despite logic saying otherwise. Thanks so much for the replies.

[AnxiousNoMore]

Consider therapy instead of wasting so much of your life in fear that you need to take endless tests. There is no reason to put your life on hold over the fear of a disease you don't have.  I can understand the initial fear being exposed to a known hiv positive person, however the tests have proven that you are neg, so you need to let go and live a normal life,