Most women are not going to be measuring their hormone levels daily, but fortunately, we don’t need to do so to be able to tell where in our menstrual cycle our body is. The hormonal changes that cause ovulation also cause other observable effects. Although everyone woman’s body has its own idiomatic ways of signaling ovulation or menstruation (mood, cramps, and breakouts are the classic examples), there are several signals which can be used by most women to understand their cycle.
Of course, these signals are not perfect, which is why in an earlier post I mentioned that they are incredibly valuable for a woman trying to achieve pregnancy and useful, but not as useful for women trying to avoid pregnancy. Depending on the regularity of your cycle, monitoring these signals may or may not be sufficient for avoiding pregnancy, and if you are in a situation where avoiding pregnancy is imperative, you should use other methods of birth control. That said, whether you are trying to achieve pregnancy, avoid it, or are not sexually active at all, tracking these signals can be a valuable way to learn what is and isn’t regular for your body. I personally wish that in my teenage years, when I had an incredibly irregular cycle, I had been educated about tracking and had spent some time understanding what my body was doing instead of being put straight on the pill to avoid the uncertainty of an irregular cycle. I expect I would have still chosen the pill eventually, but I would have had a much better idea of what to expect when I eventually wanted to achieve pregnancy.
Waking temperature
Back to the signals. The first signal is your waking temperature. After ovulation, a woman’s waking temperature shifts up by over half a degree. Given that the daily variation is generally within a few tenths of a degree, the shift is generally fairly easy to spot on a graph of temperatures. The temperature shift is due to the progesterone that is released after ovulation. Temperatures fall again when you start to bleed.
However, taking your temperature has a few weaknesses. The biggest is that your temperature shifts after you’ve ovulated. Thus, unless you have a regular cycle, this signal will not be useful for predicting when you are going to ovulate. Temperatures also can be effected by fever, alcohol the previous evening, shifting waking time (including adapting to changing time zones), and other shifts in your normal routine. Thus, waking temperature is most valuable as a confirmation that you have ovulated: once you see consistent elevated temperatures, you can conclude that you’ve ovulated, and may be able to pinpoint when, based on the quality of your data.
Cervical mucus
Cervical mucus, also called cervical fluid (because apparently some people think mucus sounds icky), is a more predictive but harder to interpret fertility signal. Rising estrogen levels eventually cause the release of the egg, and they also cause your cervix to release better quality mucus. Better, in this case, meaning a healthier environment for sperm. This is important, because after ovulation, the egg dies off rather quickly. Thick “egg white” cervical fluid allows sperm to live 3 – 5 days, so it can be ready and waiting when ovulation occurs.
Essentially, the gooier and more lubricative the fluid is, the better an environment it is. For most women, their mucus varies from nothing (dry or damp vagina), to dry and sticky, to creamy (like lotion), to egg white (which is often stretchy). The best days to have sex if you are trying to conceive are those when you have egg white mucus. If you’re trying to avoid pregnancy, you should avoid having unprotected sex when your mucus is creamy or egg white. And even if you aren’t having any sex, you should know that it’s normal for your vaginal discharge to change quite substantially.
Cervical mucus can be detected before you’ve ovulated, so in that sense, it’s more predictive than waking temperature. However, it has its own difficulties. It generally takes a few cycles to get a good sense of the different mucus qualities — the first time around, the difference between “creamy” and “sticky” is mostly guesswork, especially for women who have a small quantity of mucus.
The other difficulty is that your body can both over and under signal. One symptom of my irregular cycle was that I would have my mucus quality increase and then drop repeatedly without a temperature shift. Thus, while higher quality mucus was still a good signal of when it would be good to have sex to increase the odds of pregnancy, it was not a good sign of ovulation. On the other hand, while ovulation would always occur after my peak mucus quality, sometimes my peak was at creamy, not egg white.
Cervical position
In addition the releasing mucus, your cervix changes position in preparation for pregnancy. As you approach ovulation, your cervix goes from firm to soft, low in your vagina to high, closed to open, and non-wet to wet (because of mucus). If you can actually reach your cervix and tell from feel alone the difference between the two states, you can use this as another signal to correlate with cervical mucus. If you have ambiguous mucus, like me, this can be valuable, because there are only two states to distinguish. However, it also takes a lot of practice, and after several cycles, I did not feel like my observations were very reliable.
Conclusion
Tracking your primary fertility signals is incredibly valuable if you want to understand what your body is doing. It is also reassuring. When I would go for 50 – 100 days between periods, it helped to know whether or not I had ovulated yet, and once I finally did ovulate, to know when I would have my period. It’s also empowering to realize that your body is not just some random, unpredictable thing. You can understand it and its cycles.
Primary source: Taking Charge of Your Fertility by Toni Weschler