Tuesday, 21 February 2012

Faint Positive Pregnancy Tests... Wow

Okay this is a quick blog as my lunch is nearly over at work, I have done loads of tests and they have all been coming up with really faint BFP's, ill post some pics when I get home for work. So as far as I’m concerned they are negative because they are really faint.

Since May 2011 my periods have averaged 33 days which means that I would have ovulated on the 20/01/12 and on the 26/01/12 I had one drop of blood literally when I wiped followed by a bit of pink spotting, then brown then it turned white and has stayed white ever since (My thought is an implantation bleed). My last period was 29/12/11 and none since!! So.... as of today I would be 7 weeks pregnant if I was pregnant and should be getting strong positives by now!!

Symptoms which are irrelevant as you can get all of these with PCOS but anyway - tingling breasts and sensitive nipples but not painful like when AF is due which come and go throughout the day - veins are becoming more prominent on my breasts - Extremely bloated Uggh!! - peeing all the time which is annoying when you go 4 times in the night - slight metallic taste in my mouth - light cramps on and off - my beard is growing at a phenomenal rate!! - spots and blemishes are a lot darker and harder to cover with makeup - rashes all over my body (I had eczema as a kid) - overwhelming tiredness - very moody (my fella is not talking to me at the moment and called me an old moody cow!!..... nice!!) - very heavy discharge feels like a light AF and its very milky white, my nose is also running more, drooling, lots of ear wax and watery eyes..ewwww

So I did some research and I was shocked to find that one of the reasons for a faint positive is if you have too much HCG which can cause a false negative result and that you should dilute your urine with water and test. I will give it a try later but I doubt I am really pregnant.

A false negative pregnancy test means that the test tells the patient they are not pregnant when they really are. Why does this occur? There are four well known reasons pregnancy tests can give false negative results.

1) The most common reason is testing too early after fertilization occurs. The pregnancy hormone, hCG, is not produced until implantation occurs and it takes several days for the hCG concentrations to get high enough in blood and then urine to give a positive signal. Most devices give positive results around the day of a woman's expected period, but this can vary widely.

2) Another reason for false negative results is dilute urine. If a woman drinks a lot of fluids, the concentration of hCG in the urine will be more dilute. For this reason many doctors recommend that testing be performed on the first urine of the morning because this tends to be the most concentrated (because you probably have not drank anything all night long).

3) A very rare cause of false negative results occurs when very, very, high concentrations of hCG are present. This is called the high-dose hook effect. The hCG assays works by forming a so-called "sandwich" with two different antibodies as the "bread" and the hCG molecule as the "meat." The hook effect occurs when the hCG concentration is so high that it saturates both antibodies and there are so many molecules that the antibodies don't actually form a sandwich. This is rare because women don't normally produce enough hCG to saturate both antibodies. The hook effect should be of concern in a hospital setting, but most women should not be concerned about a hook effect with their urine. A hook effect can be confirmed if testing shows a positive result after sample dilution.

4) Finally, the other reason for false negatives was only recently described and is referred to as the "variant hook effect." This is much more common than the hook effect. As pregnancy progresses, there are actually different variant forms of hCG that begin to appear in the urine. After about 5 weeks of pregnancy (i.e. 3 weeks after the expected period) concentrations of hCG beta core fragment are higher than all other forms of hCG. This is perfectly normal. Unfortunately, the concentration of hCG beta core fragment can saturate one of the antibodies used in the assay in certain pregnancy kits, and the other antibody doesn't recognize the beta core fragment. As a result, no sandwich forms and the test is read as a negative. The farther in pregnancy a woman is, the more likely that this false negative will occur. Similar to the hook effect, the variant hook effect can be confirmed if testing shows a positive result after diluting the sample.

Posted by Ann M. Gronowski, PhD 5/8/11 - http://www.pregnancylab.net/hcg-variants/

Wow – I did not know this so I had to share it, also Coke, lemonade and coffee all produce BFP’s on pregnancy test which I found out by accident. (basically I left an old test next to take away cup which leaked coke onto the test and a strong positive came up so I googled it and found out that it was possible, I took an internet cheapy and tried it and got a faint positive like my first test... FYI the internet cheapy tests are rubbish!!)

Can anyone who gets a faint positive and then dilutes there pee and gets a strong positive let me know as it would help so many!!

Quick update! I wasn't pregnant, may have been a chemical pregnancy who knows what happened? But I had a period on the 6th March and on the 10th April"

Savannah x


  1. ivf process

    Most devices work around the day of a ladies predicted period, but this can differ widely.

  2. Thanks very helpful im also a sufferer im 26 and have all the symtoms to, also have endemetreosis no children miscarried 4 months ago and i was 5 weeks pregnant tests were all negative including clear blue tests