This week I found this really useful guide to reading and understanding OPK tests. It has been prepared by We Forgot The Sperm, and we couldn’t have said it any better ourselves!
Here’s a brief extract…
I’m seeing a lot of confusion from ladies at the moment regarding Ovulation Predictor Kits, or OPKs. As someone who has used them for some time I figured I would share my knowledge on the subject.
What are OPKs and how do they work?
OPKs (Ovulation Predictor Kits) are peesticks! Every TTC’er loves peesticks! They measure the ‘Leutenising Hormone’ (LH). LH is responsible for stimulating ovarian follicles. Before ovulation occurs, there is often a surge or dramatic increase of this hormone, which is what causes the egg to be released from the follicle. The Ovulation Predictor Kits look for that surge by measuring levels of LH in your urine. The surge in LH means ovulation within 12-48 hours.
How do I know when an OPK is positive?
We always have LH in our system, so OPKs don’t work like pregnancy tests. For an OPK to be positive, the ‘Test Line’ (the line closest to the part that you pee on) has to be as dark as or darker than the ‘Control Line’ (the line closest to the handle). If it is not as dark or darker, the test is not positive.
Below is an example of OPKs done over a cycle. Everything by the red line is negative. Everything by the green line is positive.
As you can see, there are a few occasions where the line darkens to a point and then lightens back up again. This is because LH fluctuates naturally in our systems.
Some ladies have a ‘Fade In’ pattern, where the OPK gradually goes from negative to positive, but others get absolutely no line and then BAM! Positive! We’re all different, so you have to work out what works for you…
To read the full guide, please head on over to the We Forgot The Sperm blog. Thanks for sharing ladies!
