"If you have a spike in temperature showing that you [ovulated], is there a chance that you really didn't release an egg?"
Short answer: probably not. But in order to know the answer for sure, there are a couple of things to look at. Let's talk a little bit about the role of hormones during your cycle, and why you get a temperature shift in the first place.
PROPER USE OF FERTILITY AWARENESS
Fertility awareness is not something that is usually interpreted ahead of time; it is done by letting patterns develop until they are clear enough to be confirmed. Sometimes it's hard to say if you've ovulated until your temperature has stayed above the coverline for at least three days, and sometimes it's hard to confirm something unless you have one (or hopefully two!) other signs to back you up. So, that being said, the best gift you can give yourself if you want to know if you're ovulating is to (1) fully chart all three signs, and (2) be patient while your body tells you what it's doing.
HORMONES DURING YOUR MENSTRUAL CYCLE
FSH, in turn, triggers the rise of Estrogen, which prepares your body for upcoming ovulation. Your body must produce enough Estrogen to trigger the release of LH, or Luteinizing Hormone, in the day or two before ovulation. Once this Estrogen surge has been reached, LH spikes sharply, prompting the developed follicle(s) to burst forth from one of the ovaries. Once LH has been produced, ovulation usually follows within a day or two.
After ovulation occurs, the follicle that released the egg from the ovary collapses on itself and becomes the corpus luteum. It immediately begins to release progesterone and a little estrogen, which help send signals to the body to stop producing LH and FSH. This keeps your body from releasing more eggs. Progesterone also thickens the uterine lining to prepare for egg implantation. The reason your temperature rises after ovulation is due to the increasing amounts of progesterone in your system; your body is literally warming up to prepare to "incubate" an egg. Pro + gesterone = pro (supporting) gestation (pregnancy).
Therefore, you could say definitively that if you knew your temperature rise was due to ovulation, then yes, you definitely ovulated.
I know, I know...it seems very circular and mostly obvious. If you know it's rising due to ovulation, then duh, of course you ovulated! So let's talk about how to know if that temp rise is actually from ovulation.
TEMPERATURE RISE: DID IT OR DIDN'T IT?
Your coverline is simply a line that marks .1 degree above the highest of your last five pre-ovulatory temperatures. Note that, by definition, your coverline can't be determined until after your temperature rise, and sometimes several days after.
So let's say your temperature jumped up, and has remained above the coverline, for three days. Let's also assume the following for a second:
- You have consistently charted your waking temperatures around the same time every morning (plus or minus 30 min) with more than 4 hours of consecutive sleep;
- Your temperatures are not disrupted due to alcohol consumption, extreme stress, or extreme room temperatures.
If you have experienced a temperature rise within those parameters, there's a very solid chance that you did, indeed, ovulate. Here's where the other two fertility signs come into play: they can be a great backup to help you verify if you really did ovulate. Once you ovulate, both of your other two fertility signs should change fairly drastically within a day or two. Your cervix should go from being soft, high, and open to low, firm, and closed, and your cervical fluid should go from fertile, clear, and stretchy (think raw eggwhites) to dry, sticky, or creamy. If your temperature jumps up and you notice these other two signs changed as well, it's an excellent confirmation of actual ovulation.
The biggest question I get regarding the temperature jump is a request to look at someone's chart 1 or 2 days after ovulation. While you can make a fairly accurate guess at whether ovulation happened or not, usually you just have to wait and see. Ovulation is something that is usually only absolutely confirmed in retrospect, meaning it can sometimes be hard to tell for sure until three or more days after it happens. That's why it's so important to track your other fertility signs to tell you when you are approaching ovulation, not already past it.
No one (especially someone who is TTC) likes to be told to wait and see--there's already plenty of waiting as it is!--but often, with ovulation, that is exactly what you have to do. If you're not sure if you actually ovulated, give it a day or two. See if your temps stay up and your other fertility signs dry and close up. And make sure you're keeping an eye out for ovulation before it happens, not just after!
OTHER REASONS FOR ELEVATED TEMPERATURES
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