- There are signs that can help you track and predict ovulation, including changes to your body temperature and vaginal discharge.
- In a typical 28-day menstrual cycle, ovulation occurs at around day 14.
- Ovulation predictor kits detect levels of luteinising hormone (LH) in your urine and can help you know when ovulation is likely to occur.
- Having sex in the days leading up to and the day of ovulation will increase your chance of conceiving.
- If you are trying to get pregnant, see your doctor for a pre-conception health check.
When am I most fertile?
You are most likely to conceive during the 5 days before ovulation, along with the day you ovulate. Sperm can live up to 5 days inside your body, so if you have sex up to 5 days before your egg is released, you can get pregnant.
After ovulation, your egg can only live for 12 to 24 hours. After this time is up, your chance of getting pregnant is virtually zero until your next menstrual cycle.
Your chances of getting pregnant are at their highest in the 3 days leading up to and including ovulation.
How can I predict ovulation?
Ovulation usually happens about halfway through your menstrual cycle. This is about 14 days before the first day of your next period in a typical 28-day cycle, but the exact time can vary. Signs that you are about to ovulate can be subtle. However, there are some things you can pay attention to and track over time to help you predict your fertile window.
Changes in mucus
Around the time of ovulation, you may notice your vaginal discharge is clear, stretchy and slippery — similar to egg whites. After ovulation, when the chances of becoming pregnant drop, vaginal discharge tends to become cloudy and thick, or disappear entirely.
Changes in body temperature
When you’ve just ovulated, your body temperature may increase very slightly, by about half a degree Celsius. If you’re using temperature to keep track of when you are most fertile, you need to use a special thermometer to take your temperature every morning before you get out of bed. If you record the readings every day using a graph or a spreadsheet, it’s possible to learn your pattern over time. The time when you are most fertile is 2 to 3 days before the rise in temperature.
There may be other signs that you are near the time of ovulation, such as mild abdominal cramps, breast tenderness or increased sex drive. However, using these signs to predict when you’re fertile is not the most reliable method.
Using ovulation calculators and kits
Ovulation calculators and kits can also help you predict ovulation.
Ovulation calculators are available on websites such as www.yourfertility.org.au. Use the date of your last period and the length of your cycle to predict when you are likely to be most fertile.
Home ovulation predictor kits are available from pharmacies. They test for a rise in the level of a hormone called luteinising hormone (LH) in your urine. You should use the kit a few days before your predicted ovulation day. A positive result indicates you will ovulate within the next 24 to 36 hours.
Your doctor can also arrange a blood test to check your progesterone levels, which can be used to detect ovulation.
What else should I think about if I’m trying to conceive?
If you are trying to get pregnant, there are some other things you should consider, such as:
- taking a folate supplement
- maintaining a healthy diet
- making sure your vaccinations are up to date
Most healthy couples will conceive within a year of trying. If you are under 35 years of age and have been trying to conceive for a year without success, see your doctor to discuss your options.
If you or your partner are over 35, you might like to see your doctor after trying to conceive for 6 months, as fertility can decrease with age.
Where can I get more information about ovulation?
You can find more information from:
- Your Fertility for more information on ovulation and the fertile window.
- Jean Hailes for Women’s Health for more information on things that can be helpful to know, when you start trying for a baby.
- Your doctor
Speak to a maternal child health nurse
Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available 7am to midnight (AET), 7 days a week.
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Last reviewed: October 2022