Top positive review
229 people found this helpful
Interesting experiment about light lines and a FMU rant
on December 14, 2011
1st of all, these are great. I've used tons of them. I've never, ever had a false positive or even an "evap." These registered positive (albeit faintly) at 10 dpo, a day before 1st Response Digital Gold was positive. They are as good, if not better, than the $20/2 pack HPTs I'd sell you if you walked into my pharmacy.
For women who keep testing after getting a positive: these tests do take quite a while (many days) to get dark (as dark or darker than the control line). This was worrying me, so I decided to do an experiment (despite what you've read, the lines SHOULD get darker over time). I peed in a cup and took a test. Then I diluted it 1:1 with water, and took a test. Then I diluted that 1:1 with water AGAIN and took a test. All three were EXACTLY the same. All positive, but not any darker or lighter. This means that, at least within this range (about 20 dpo), a four-fold difference in HCG will not result in a lighter or darker test. This was very reassuring. These do get darker, but much, much more slowly than other tests. Do not worry too much about them not getting very dark quickly.
Now, please let me dispell the FMU (first morning urine) myth, which drives me crazy. It's just not true. Here's why: we've been told to use FMU (or, at least to hold our urine for a long time) for better results. Not true. HCG blood levels in early pregnancy increase with time. So, your blood level last night was lower than your blood level this morning. The FMU in your bladder this morning is a mixture of last night's urine, this morning's urine, and ever thing in between. The "old" urine from last night has a lower HCG that this morning's urine and is therefore "diluting" the HCG. You'd do much, much better to empty your bladder (without drinking any more liquids) and wait until you can go again. Think about it. Holding your urine doesn't concentrate it; it just mixes old urine with new urine. The only thing that concentrates it is drinking less, combined with peeing MORE frequently (not holding it).