Ovulation is the release of a mature egg cell (an ovum in medical terminology), ready to be fertilized, from one of your ovaries. This happens once per menstrual cycle.
If the egg cell isn’t fertilized by a sperm cell within 24 hours after ovulation, it dies, and your chances of conception are gone in that cycle.
Luckily, sperm cells can live inside your body for a while before they meet and fertilize the egg. This means that you can get pregnant by having intercourse a few days before ovulation, not only on ovulation day itself.
However, the monthly window of opportunity for conception is still relatively short. Knowing when you are ovulating, and timing intercourse accordingly, is therefore one of the most important things you can do to increase your chances of getting pregnant quickly.
When do I ovulate?
We are often told that the menstrual cycle is 28 days long, and that ovulation occurs on the 14th day of the cycle. These are just statistical averages, however. Cycle length and ovulation day varies considerably from one woman to another, and from one cycle to another.
Online ovulation calculators or apps can give you an estimate for when your ovulation is likely to occur. Many women also experience physical signs and symptoms before ovulation, such as an increase in sexual desire, ovulation pain (a cramp or sharp pain in one side where the ovary is located) or tender breasts.
None of these indications are very reliable, however, and if you want to identify your ovulation day as precisely as possible, you should try one of the following methods.
Use ovulation tests
The fastest and easiest way to identify your ovulation day is by using ovulation tests, or ovulation predictor kits.
Ovulation tests detect the surge of luteinizing hormone (LH), which your body produces 24 to 36 hours before ovulation. A positive ovulation tests means that you are at your most fertile, and having intercourse at that time means the highest chances of getting pregnant.
Observe your cervical mucus
Through most of your cycle, your cervix (the lowest part of your uterus, located in your vagina) produces a thick mucus that sperm can’t penetrate. This mucus protects the uterus from infection by preventing bacteria from entering the vagina, just like the mucus of your respiratory tract protects your lungs.
Right before ovulation, however, increased levels of the hormone estrogen in your body will cause the cervical mucus to become thinner, clearer and more stretchy.
This fertile mucus, which looks and feels a lot like raw egg white, allows the sperm to swim through the cervix, into the uterus, and up to the fallopian tubes where conception may take place.
Observing these changes in your cervical mucus can help you find out when you are at your most fertile.
Chart your basal body temperature (BBT)
Basal body temperature (BBT) is the temperature of your body in full rest. Immediately after ovulation, a hormonal change (increased production of progesterone) causes this temperatures to slightly rise.
By measuring your body temperature every morning and tracking the results, you can see this shift from lower to higher temperatures and deduce with relative certainty on which day you ovulated.
Because the temperature change can’t bee seen on your chart until after ovulation, when you’re no longer fertile, it cannot help you with intercourse timing. But it will help you get more familiar with your cycle, confirm that you actually are ovulating (or alert you that you’re not), and identify whether your luteal phase (the second part of your cycle) is long enough to sustain implantation of a fertilized egg.
Observe your cervical position
In the same way as the cervical mucus changes under the influence of different hormones at different times in your cycle, the cervix itself changes position and texture. You can track these changes in your cervix by how it feels to the touch.
Here’s how to do it:
- Wash your hands. If your nails are long, you may want to wear latex gloves to avoid scratching yourself.
- Squat down, or stand with one foot raised on a stool, bathtub or similar.
- Insert your middle finger into your vagina until you feel your cervix towards the back. You should be able to move your finger all the way around the cervix. You may also feel a “dent” in the middle; this is the cervical opening where sperm cells can enter your uterus.
- Note how deep in your vagina the cervix sits. How much of your finger do you need to insert in order to reach it? As ovulation gets closer, the cervix is pulled further up into the body and can be harder to reach.
- Note how soft it feels. Close to ovulation, the cervix will feel about as soft as lips. Early in the cycle and after ovulation, it will be firmer, like the tip of your nose.
These changes to the cervix can be very subtle, so you should check every day in order to become familiar with it and more easily feel the small changes occurring from day to day. Check your cervix in the same position and at the same time each day, i.e. in the shower every morning.
Checking your cervix alone is not a very accurate way to predict ovulation, but can be a helpful indicator when combined with information from monitoring other ovulation signs.