Although it may take some detective work — and may be a little off-putting to some — learning to detect changes in your cervical mucus is an easy and highly effective of way of predicting ovulation. According to a recent study, it's a more accurate way of predicting ovulation than BBT, although it can be used in conjunction with it.
The mucus released by the cervix serves different purposes. When you're not ovulating or approaching ovulation, cervical mucus prevents sperm from getting into the uterus at a time when you couldn't become pregnant anyway. As you near ovulation, your cervix secretes an increasing amount of mucus, and when you're at your most fertile, your cervical mucus is stretchy and clear, like the consistency of egg whites. At this point, the mucus actually protects the sperm and helps it in its journey toward the egg. Check out pictures of a cervix with daily changes throughout the menstrual cycle HERE.
For a woman with a 28-day cycle, the pattern of changes in her cervical mucus would look something like this:
- Days 1-5: Menstruation occurs.
- Days 6-9: Vagina is dry with little to no mucus.
- Days 10-12: Sticky, thick mucus appears, gradually becoming less thick and more white.
- Days 13-15: Mucus becomes thin, slippery, stretchy, and clear, similar to the consistency of egg whites. This is the most fertile stage.
- Days 16-21: Mucus becomes sticky and thick again.
- Days 22-28: Vagina becomes dry.
However, your cycle will probably differ from this pattern, perhaps significantly, which is why it's useful to mark changes on your own fertility chart.
Ideally, you should check your cervical mucus daily, possibly every time you go to the bathroom. If you rub some toilet paper or your fingers — after washing your hands — over the opening of your vagina, you should be able to detect cervical mucus. Examine the color and consistency between your fingers and make sure to note it down.
Why check cervical mucus? Because your basal body temperature (BBT) usually indicates ovulation only after it has happened, checking the cervix or the cervical mucus can help predict impending ovulation. The cervical mucus changes several days before ovulation by becoming more abundant and stretchy (often called egg white cervical mucus or EWCM). Within one to two days after ovulation, these typical changes disappear.
You can feel your cervix by gently inserting one or two fingers into the vagina and palpating the cervix at the end of the vagina. Prior to and after ovulation, the cervix feels firm, low, closed, and dry. Around the time of ovulation, the cervix feels soft, high, open, and wet.
As a side note, you cannot diagnose a pregnancy early on from examining the cervix, because these changes are too subtle to pick up and usually do not appear until well after you miss your period.
Using an ovulation predictor kit (OPK) can also help you predict when you are about to ovulate. The OPK is a test that checks your urine for the presence of luteinizing hormone (LH). Normally, LH is in a steady state, at a low level (negative test). But when it rises very quickly (LH surge) it stimulates the developing egg (follicle) and ovulation (release of the egg) follows shortly thereafter. Ovulation usually happens within 12-36 hours after the OPK first turns positive.