Ovulation Calculator

Boost your chances of getting pregnant with our ovulation calculator

Whether you're trying to get pregnant or currently avoiding pregnancy, an ovulation calculator can help you know your menstrual cycle better so you can track ovulation and when you are most fertile. Try our ovulation calculator to discover your unique cycle and when the best time to conceive may be.

Ovulation calculator

When is the best time to get pregnant?

To maximise your chance of getting pregnant it can be best to look at the days you're most fertile as you can only get pregnant on the few days of each cycle around ovulation, when an egg is released. If you're wondering how much sex you need to be having to get pregnant, the answer is as much as possible and you should aim to have regular intercourse (that's every two to three days) during these days to increase your chances of conception.

It's also worth remembering that if you've had sex in the seven days before ovulation, it's possible to get pregnant because sperm can live inside you for up to seven days and fertilise the egg when it's released.

For some people, it can take a while to get pregnant. On average, around 84 per cent of couples will get pregnant within a year of trying and 92 per cent will do within two years, with 17-20 per cent of couples will get pregnant within that first cycle.

If you're using this calculator as a form of natural contraception for birth control, avoid having sex on the days you're most fertile or use an extra form of contraception such as condoms.

How does your menstrual cycle work?

While the average menstrual cycle lasts 28 days, anything from 22 to 36 days is perfectly normal.

Right now, your body is shedding a combination of the lining of your womb (called the endometrium) and actual blood. You won't know whether your egg has been fertilised for another month but can still do things to focus on your fertility, such as eating a healthier diet and reducing your alcohol and caffeine intake.

Week 2: The lining of your womb thickens ready for fertilisation, and eggs begin to mature in the ovary.

Week 3: This week, your levels of lutenising hormones (LH) and follicle stimulating hormone (FSH) will rise, stimulating the production of follicles in your ovaries. Usually, one ovulation follicle will become larger than the others and will produce the egg. That follicle will also start to produce oestrogen - the clever hormone that tells your body to start thickening the lining of the womb for implantation. If sperm is present at the moment of ovulation, or 24 hours after the egg is released, the egg may be fertilised.

Week 4: If fertilised, the egg will now travel from the fallopian tube to your uterus and divide into 16 identical cells. If the egg has not been fertilised, the egg is re-absorbed, hormone levels drop and your menstrual cycle begins again with your next period.

What if I have irregular periods?

If you can't count how long your cycle is or work out when your period is due because of irregular periods then it can be difficult to determine when you are ovulating. The good news is that there are other ways of working out when you are ovulating.

How to spot the signs and symptoms of ovulation

Some women can spot physical signs of ovulation occurring. Some symptoms include:

Ovulation discharge: This cervical mucus best described as similar to egg white - slippery and clear.

Temperature: Your basal body temperature (BBT) rises about half a degree after ovulation has occurred. You can buy a special basal thermometer to help you chart when ovulation happens. Take the reading before you get out of bed every day to ensure it’s as accurate as possible.

Ovulation pain: Some women may experience Mittelschmertz or “Middle Pain”, as 'stitch-like' pain on one side or towards the bottom of the tummy.

Ovulation bloating: Hormone changes during your menstrual cycle can result in slowed digestion and bloating during ovulation.

Ovulation bleeding: as your estrogen levels fluctuate you may experience some light bleeding or spotting. This results in a slightly pink discharge.

Basal body temperature: Your BBT can increase slightly when ovulation takes place, due to an increase in the hormone progesterone, so can therefore become a useful tool for natural family planning when tracking ovulation and trying for a baby.

Conception and sex: How to boost your chances of conceiving

Now you know when you're most fertile, make the ovulation calculator results work for you and boost your chances of conceiving no matter where you are in your menstrual cycle.

Try the best sex positions to get pregnant: To increase your chances of getting pregnant, is it advised to have sex around the time you are ovulating. In this case, you should have sex for the three days leading up to ovulation and possibly on the day you expect to ovulate, too.

Top up on folic acid: 400mg of folic acid is recommended if you’re trying to conceive and into your first trimester.

Eat fertility superfoods to get pregnant: super-simple tweaks to your diet will provide your body with the fertility-boosting nutrients you need to grow a baby.

Keep it in perspective: Most couples having regular sex twice or more a week will get pregnant within a year. However, it can be hard to ignore the worry that there might be something wrong if you don’t get pregnant straight away. If you're concerned and it's been over a year with no luck, visit your GP.

How to use ovulation test kits

Ovulation calculators (also known as fertility calculators) are a good indicator of where you are in your menstrual cycle, however, every person is unique and so is their cycle, so it's important to take the results with a pinch of salt. The results may also be skewed if you are unsure when exactly your last period was, you have just come off the pill or your periods are irregular. If you’ve been trying for a while, talk to your GP.

One to two days before ovulation occurs, the body produces a surge of the luteinizing hormone (LH) which can be detected in urine. Ovulation predictor kits (OPKs) look for this surge and alert you to its presence - digital OPKs will display a symbol such as a smiley face.

This means it is likely you’re about to ovulate, so it’s recommended you have sex on the day of the surge, as well as the two days after. Play it safe by adding one more day onto this, just in case you’ve ovulated a day later than expected.

There are other ways of tracking ovulation, including a number of helpful apps. These ovulation apps can help you track your cycle and learn more about your ovulation patterns allowing you to get to know your body better from your phone or tablet.

Support when trying to conceive

Trying to conceive can be an emotionally draining experience, not just for you, but for your partner, too. Fertility Network UK offers support groups where you can share your ttc journey with others who are going through the same experience. There is also a range of helplines to help mums who need support.

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