Aa
Something interesting!
I was looking to see it there was a chance that the OPK is picking up hCG. I got another very dark OPK today and cant understand what it would be so dark after I had a serge of LH with that positive yesterday. here is what I found...
let me know what your thought are on this!
Home pregnancy tests work by detecting the presence of Human Chorionic Gonadotropin, HCG. Today's home pregnancy tests can detect HCG in the urine of pregnant women even before a period is missed.
If OPKs detect LH and HPTs (home pregnancy tests) detect HCG, why would anyone think you could use an OPK as an HPT?
HCG and LH
Let's take a closer look at LH and HCG. Both hormones are glycoproteins, meaning they consist of a protein with a sugar attached to it. If you remember from high school biology, proteins can be broken down into chains of amino acids. HCG and LH can be broken up into two units or "chains", one subunit called alpha and the other beta. If you look at the alpha subunit, the chains of amino acids are identical. In fact, HCG's alpha subunit is identical to the hormones LH, FSH, and TSH, all produced in the pituitary gland. HCG is the only one of these alpha subunits that is not produced by the pituitary, but rather the placenta.
We know that the alpha subunits are identical, but what about the beta subunits? The beta subunits of LH and HCG are also very similar in structure. Not only are they similar in structure, they are also similar in function. This is why you will see HCG injections used as an infertility treatment. HCG injections are used to replicate the LH surge of the menstrual cycle to induce ovulation.
Where HCG and LH differ is HCG's beta subunit has about 30 extra amino acids attached to the end of it. Home pregnancy tests are designed to specifically look for this HCG beta subunit.
OPKs as HPTs
OPKs are intended to detect LH. Since LH and HCG are nearly identical, OPKs will also detect HCG. The reverse is not true for HPTs. Home pregnancy tests will only detect HCG. So in theory, yes, and OPK could detect pregnancy.
Reasons not to use an ovulation prediction kit for a home pregnancy test
OPKs cannot distinguish between LH and HCG. Getting a positive OPK only confirms that you have either LH or HCG in your system.
It is important to discuss some of the other differences between OPKs and HPTs. LH is present in the body at all times. HCG is not. WIth OPKs, they detect a sudden increase or "surge" of LH. The typical amount of LH that is in the body at any given time is between 5-20 mIU. Therefore an OPK is looking for a surge above this typical amount. Most OPKs look for a level around 30-40 mIU. However, there are some tests that detect lower levels of LH. You can easily see how testing with a more sensitive OPK could result in a false positive. Newer OPKs look at a combination of LH and estrone-3-glucuronide, E3G, which may be helpful to further pinpoint ovulation.
Home pregnancy tests on the market are very sensitive testing at 25 mIU and below. This is more sensitive that the typical OPK. So even if you could get a positive on an OPKs, you would most likely get one sooner on a home pregnancy test. Because OPKs are designed to detect LH and not HCG , it is not recommended to use an OPK for an HPT.
let me know what your thought are on this!
Home pregnancy tests work by detecting the presence of Human Chorionic Gonadotropin, HCG. Today's home pregnancy tests can detect HCG in the urine of pregnant women even before a period is missed.
If OPKs detect LH and HPTs (home pregnancy tests) detect HCG, why would anyone think you could use an OPK as an HPT?
HCG and LH
Let's take a closer look at LH and HCG. Both hormones are glycoproteins, meaning they consist of a protein with a sugar attached to it. If you remember from high school biology, proteins can be broken down into chains of amino acids. HCG and LH can be broken up into two units or "chains", one subunit called alpha and the other beta. If you look at the alpha subunit, the chains of amino acids are identical. In fact, HCG's alpha subunit is identical to the hormones LH, FSH, and TSH, all produced in the pituitary gland. HCG is the only one of these alpha subunits that is not produced by the pituitary, but rather the placenta.
We know that the alpha subunits are identical, but what about the beta subunits? The beta subunits of LH and HCG are also very similar in structure. Not only are they similar in structure, they are also similar in function. This is why you will see HCG injections used as an infertility treatment. HCG injections are used to replicate the LH surge of the menstrual cycle to induce ovulation.
Where HCG and LH differ is HCG's beta subunit has about 30 extra amino acids attached to the end of it. Home pregnancy tests are designed to specifically look for this HCG beta subunit.
OPKs as HPTs
OPKs are intended to detect LH. Since LH and HCG are nearly identical, OPKs will also detect HCG. The reverse is not true for HPTs. Home pregnancy tests will only detect HCG. So in theory, yes, and OPK could detect pregnancy.
Reasons not to use an ovulation prediction kit for a home pregnancy test
OPKs cannot distinguish between LH and HCG. Getting a positive OPK only confirms that you have either LH or HCG in your system.
It is important to discuss some of the other differences between OPKs and HPTs. LH is present in the body at all times. HCG is not. WIth OPKs, they detect a sudden increase or "surge" of LH. The typical amount of LH that is in the body at any given time is between 5-20 mIU. Therefore an OPK is looking for a surge above this typical amount. Most OPKs look for a level around 30-40 mIU. However, there are some tests that detect lower levels of LH. You can easily see how testing with a more sensitive OPK could result in a false positive. Newer OPKs look at a combination of LH and estrone-3-glucuronide, E3G, which may be helpful to further pinpoint ovulation.
Home pregnancy tests on the market are very sensitive testing at 25 mIU and below. This is more sensitive that the typical OPK. So even if you could get a positive on an OPKs, you would most likely get one sooner on a home pregnancy test. Because OPKs are designed to detect LH and not HCG , it is not recommended to use an OPK for an HPT.
Mikaleen- that's funny about the time being afternoon somewhere else... good point though...lol
So i tested again this morning and and got my 5th day of having a positive. it didn't come up dark as fast as yesterday mornings but it was a positive before the 8 min time.
and soon after the 8 min time it was even darker. if ia m testing positive in the AM and in the PM then there has to be something wrong.
I am using Answer sticks, does anyone know how much LH it picks up before becoming a positive. last month I used the Answer ones but the ones in the plastic casing. I would imagine they are the same right?
So i tested again this morning and and got my 5th day of having a positive. it didn't come up dark as fast as yesterday mornings but it was a positive before the 8 min time.
and soon after the 8 min time it was even darker. if ia m testing positive in the AM and in the PM then there has to be something wrong.
I am using Answer sticks, does anyone know how much LH it picks up before becoming a positive. last month I used the Answer ones but the ones in the plastic casing. I would imagine they are the same right?
Yesterday and the day before I opk'd in the afternoon around 2, and I got a line that wasn't quite as dark as the control. Just for kicks today I did it this morning and immediately got a line that was darker than the control. It was at 9am. Tonight at 6 it was back to the way it was yesterday. I am going to see what happens tomorrow morning. It says to test in the afternoon because most women have they're surge in the morning but it takes a couple hours to show in the urine. I figure though my afternoon is still morning for people on the west coast, so how can they say when women have their surge? Anyway, good luck and I hope your next $ test is a bfp!
I did another OPK this evening and another positive. I gave in and got the $$tree pregnancy test but it was a negative like I was expecting.
I am curios as to what the morning will bring with another OPK.
I am curios as to what the morning will bring with another OPK.
I had read about that before too. It is pretty interesting how that all works. I'm praying for you and bam to get your BFP's this month. SSBD
nunu - I got my EWCM on Wednesday, then got a + OPK Thursday, but EWCM was gone. Yesterday's OPK was negative, so I'm sure I caught my surge. I was in a considerable amout of pain yesterday and BD was just awful! I'm hoping that means that my cervix was in the right position. I'm also in pain today, but not as bad. I wouldn't classify the pain necessary as O pain, but I for sure know that something is going on. I just hope I'm not releasing TOO many eggs - LOL. I feel confident in our timing, so I guess I'm pretty hopeful for this cycle. I'm trying not to get too hopeful, as I'll be devastated when AF comes.
I'm worried about the CD27 Clomid check when I will get the pelvic exam to check for cysts. I would be 10DPO on that day and too early to POAS. I asked my friend who works in pediatrics, and she didn't think it would do any harm.
I wish I had a u/s machine at home, so I could see on a daily basis exactly what was going on :p
I'm worried about the CD27 Clomid check when I will get the pelvic exam to check for cysts. I would be 10DPO on that day and too early to POAS. I asked my friend who works in pediatrics, and she didn't think it would do any harm.
I wish I had a u/s machine at home, so I could see on a daily basis exactly what was going on :p
this morning the line came up dark VERY fast. w mornings ago the line was darker then yesterday it was same color then this morning the darkest line yet. I just cane imagine that it is testing positive for hCG unless I ovulated just after AF ended.
so maybe i just released two eggs!!!!!!
I don't know. I think Ill go get a $$tree test today... just one though. then ill just leave it until a week then test again. (yea right... do you think I can do that!!!! lol)
so maybe i just released two eggs!!!!!!
I don't know. I think Ill go get a $$tree test today... just one though. then ill just leave it until a week then test again. (yea right... do you think I can do that!!!! lol)
I'm praying for you nunu!! Wouldn't it be fantastic if we both got our BFP's and could be belly buddies :)
With my first pregnancy I was just dying to know if I was pregnant or not, and I couldn't stand waiting 2 weeks to take a HPT. I was on the internet and I read that same exact thing online, that you can get a + ovulation test, but it not show up on HPT test that soon. I took one of my ovulation tests and got a faint line (a dark faint line), which got me excited because after I ovulated I wasn't getting any lines, so I knew something was there! Sure enough...several days later I took a HPT and it was positive! Good luck to you!
just found why you shouldnt test in the Am...
The best time to test is 2 p.m., or as close as possible. Anytime between noon and 8 p.m. is fine, first morning urine is not recommended. The reason for this is that most women experience a surge in the morning, but it can take 4 hours for it to show up in your urine.
so if i am getting a positive in the AM then it s a positive because it didnt take a few hours to show up. so now its 4 days in a row ive had a AM positive!!!!
The best time to test is 2 p.m., or as close as possible. Anytime between noon and 8 p.m. is fine, first morning urine is not recommended. The reason for this is that most women experience a surge in the morning, but it can take 4 hours for it to show up in your urine.
so if i am getting a positive in the AM then it s a positive because it didnt take a few hours to show up. so now its 4 days in a row ive had a AM positive!!!!
the month I got pregnant and the first time I used OPK I got a positive for two or three days as well.... maybe this is my months. :-)
I had a similar thing happen the month I got my BFP. My OPK was actually + for 3 days, so I was sure I had completely missed O day. DH and I only BD'd twice, and the days were weird. I guess it worked since I know I got pregnant that month. Maybe this is your body's way of making up for all the he** you have been going through these past few months. Good luck, and definitely keep up the BDing ;)
I wonder how dark hCG would show up on an OPK then!
remember last month when i never got a positive, then this month ive had two mornings when i was the same color then yesterday it was way darker. even this afternoons one was close to if not the same color. I haven't found what a test would do after the surge was over. I wold imagine it would go way light again right?
last month i used two brands, Answer and the internet ones and when I tested them at the same time the showed the same result.
remember last month when i never got a positive, then this month ive had two mornings when i was the same color then yesterday it was way darker. even this afternoons one was close to if not the same color. I haven't found what a test would do after the surge was over. I wold imagine it would go way light again right?
last month i used two brands, Answer and the internet ones and when I tested them at the same time the showed the same result.
I got this off of peeonastick.com:
Regarding OPK Sensitivity: OPK's are not like HPT's. Most women want HPT's that detect as little hCG as possible, because hCG is only produced during pregnancy*. Therefore, the more sensitive the HPT, the earlier it can detect pregnancy.
OPK's measure LH, which a hormone that is always present in the female body in some quantity. This hormone surges 12-48 hours before ovulation. In women of normal fertility, a "surge" (indicating ovulation is near) means at least 20 mIU/mL of LH is present. The vast majority of women experience a surge of 40 or more mIU/mL. Since a surge builds very quickly, a woman may go from an insignificant amount of LH to 40 mIU literally within an hour or so.
Therefore, an OPK that measures 20-40 mIU is adequate, and a more sensitive OPK (20 mIU) does not offer any real benefit over a less sensitive one (40 mIU.) It's possible that a woman may experience a "slower" surge, and "linger" at 20 before shooting up to 40 the next day. (This may differ from cycle to cycle for the same woman. It has no physiological significance.)
However, I am adding sensitivities to the chart below because some women may alternate brands of tests. I noticed that when I use a more sensitive OPK (20 mIU) I can detect ovulation approximately 36-48 hours before the fact; using a less sensitive one (30-40 mIU) I have only 24 hours' notice. If you happen to use 2 brands within the same cycle, this difference in sensitivity can prove confusing.
*A non-pregnant woman may have up to 2.5 mIU/mL of hCG in her system. This level is not detectable by home pregnancy tests and is, for HPT purposes, insignificant. Otherwise, hCG production is exclusive to pregnancy . . . in low levels (up to 9.5 mIU) during menopause . . . and with some rare forms of cancer
Regarding OPK Sensitivity: OPK's are not like HPT's. Most women want HPT's that detect as little hCG as possible, because hCG is only produced during pregnancy*. Therefore, the more sensitive the HPT, the earlier it can detect pregnancy.
OPK's measure LH, which a hormone that is always present in the female body in some quantity. This hormone surges 12-48 hours before ovulation. In women of normal fertility, a "surge" (indicating ovulation is near) means at least 20 mIU/mL of LH is present. The vast majority of women experience a surge of 40 or more mIU/mL. Since a surge builds very quickly, a woman may go from an insignificant amount of LH to 40 mIU literally within an hour or so.
Therefore, an OPK that measures 20-40 mIU is adequate, and a more sensitive OPK (20 mIU) does not offer any real benefit over a less sensitive one (40 mIU.) It's possible that a woman may experience a "slower" surge, and "linger" at 20 before shooting up to 40 the next day. (This may differ from cycle to cycle for the same woman. It has no physiological significance.)
However, I am adding sensitivities to the chart below because some women may alternate brands of tests. I noticed that when I use a more sensitive OPK (20 mIU) I can detect ovulation approximately 36-48 hours before the fact; using a less sensitive one (30-40 mIU) I have only 24 hours' notice. If you happen to use 2 brands within the same cycle, this difference in sensitivity can prove confusing.
*A non-pregnant woman may have up to 2.5 mIU/mL of hCG in her system. This level is not detectable by home pregnancy tests and is, for HPT purposes, insignificant. Otherwise, hCG production is exclusive to pregnancy . . . in low levels (up to 9.5 mIU) during menopause . . . and with some rare forms of cancer
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