Ovulation

Ovulation most commonly happens in the middle of your menstrual cycle. Working out when you’re ovulating can be helpful when you’re trying to conceive, as your most fertile days are the days leading up to ovulation. It can be difficult to pinpoint exactly when you’re ovulating, but your body does show signs. You can track and chart the common symptoms of ovulation like changes to your basal body temperature and cervical mucus to work out when you’re ovulating and when your fertile window is. Learn what the signs of ovulation are and how to spot them.

What is ovulation?

Ovulation is when one or more eggs are released from one of your two ovaries. This happens towards the end of your fertile window, between periods.

Each month, a surprisingly large range of between three and 30 eggs mature inside your ovaries (Knudtson and McLaughlin 2019). The ripest egg is released and swept into one of your fallopian tubes. Your fallopian tubes connect your ovaries to your womb (uterus).

Your ovaries don’t necessarily take it in turns to release an egg. It just happens at random.

How does ovulation influence when I can get pregnant?

To become pregnant naturally, one of your eggs and your partner’s sperm have to meet in your fallopian tube. Your egg survives no more than 24 hours after you’ve ovulated (NHS 2018). So the meeting of egg and sperm has to occur within this time.

However, sperm can survive in your vagina, womb or fallopian tubes for up to seven days, fertilising the egg when it’s released (NHS 2018).

This means that you don’t have to time sex to the exact moment you ovulate to get pregnant. You actually have a fertile window of about six days (NICE 2017, NHS 2019a).

This window includes the five days before and the day of ovulation itself (NICE 2017). If you have sex every two days or three days during your fertile window, your freshly ovulated egg has the best chance of meeting live, healthy sperm and being fertilised (NICE 2017, FPA 2018).

When do you ovulate?

Regardless of how long or short your menstrual cycle normally is, ovulation usually occurs about 10 to 16 days before your next period starts (FPA 2018, NHS 2019b).

For example, say you have a regular 28-day cycle. Count the first day of your last period as day one. Your fertile window is likely to be around days 10 to 16 (NHS 2018).

However, a lot of women have an irregular cycle. If this applies to you, the time from the first day of your last period to ovulation can vary from one month to the next (FPA 2018).

What are the signs of ovulation?

You can start to notice signs that you’re fertile about five days before you ovulate. Working out your fertile window using your cycle dates alone is not an exact science. This is why learning to spot your body’s fertile signs can help.

The main signs and symptoms of ovulation include:

• changes to your cervical mucus (NHS 2019b)
• increased body temperature (NHS 2019b)
• an ache in your belly (NHS 2019b)
• tender breasts (NHS 2019b)
• feeling more attractive or sexy than usual (Cantú et al 2014, Jones et al 2018)

Changes in cervical mucus

Cervical mucus is the discharge that you see in your knickers or on toilet tissue when you go for a wee.

Changes in your cervical mucus can signal when you are fertile and close to ovulating. They are caused by the rising levels of the hormone oestrogen in your body (FPA 2018).

You're at your most fertile when your mucus becomes clear, slippery, and stretchy (FPA 2018, NHS 2019b). It’s a bit like raw egg white. This fertile mucus speeds the sperm on its way up through your womb. It nourishes and protects the sperm as it travels towards your fallopian tubes to meet your egg.

After ovulation your cervical mucus gradually goes back to being thick and sticky (FPA 2018).

See our photo gallery to check how cervical mucus changes throughout your cycle.

Some women try charting their cervical mucus and basal body temperature  to monitor the changes and work out when they’re ovulating.

Cramps or an ache in your belly

About one in five women can actually feel something happening in their ovaries around ovulation (Jacobson 2019). This can range from mild achiness to painful twinges. Some women feel ovulation as a one-sided backache or a tender area. The condition – called Mittelschmerz, which means ‘middle pain’ (FPA 2018) – may last anywhere from a few minutes to a couple of days (NHS 2019c).

If you notice these sensations at roughly the same time each month, check your cervical mucus. Ovulation cramps or pain can be a useful guide to when you’re fertile.

Feeling sexy

Many women say that they feel more sexy around ovulation. There are even studies to suggest that hormones may help to make women feel more desirable, flirty or sociable on some days than on others (Cantú et al 2014, Jones et al 2018, Suschinsky et al 2014). One small study even found that women are more drawn to wearing flattering clothes around the time of ovulation (Zhuang and Wang 2014).

There isn’t enough good evidence to be sure of this link though (Arslan et al 2018, Jones et al 2018, Stern et al 2020). So, how sexy you feel, or don’t feel, isn’t a very reliable way to work out whether you’re ovulating or not.

Try our ovulation calculator to help you work out when your fertile window is likely to be.

Some women use ovulation predictor kits to pinpoint their most fertile time. Most of these kits test for the peak of the luteinising hormone, or LH surge, which is the actual trigger for egg release. You could use these to find out when you are most fertile during your menstrual cycle (NHS 2019b), although using them to time sex won’t necessarily increase your chances of getting pregnant (NICE 2019).

How can I increase my chances of getting pregnant?

Regular sex throughout your cycle gives you the best chance of conceiving (NICE 2017). Try to have sex every two to three days (NICE 2017). Then sperm with good motility will be in the right place whenever you ovulate.

Having sex when your cervical mucus is wet, slippery, and most receptive to sperm will also increase your chances of conception (NHS 2019b). And you’ll be happy to know that the odds are with you.

One in three couples who are having sex two to three times per week will conceive within a month (Tommy’s 2018).

More than eight out of ten women aged under 40 who have regular sex without using contraceptives will get pregnant within a year (FPA 2018, NICE 20172019). Of those women who don't become pregnant after a year, half will conceive within two years (NICE 2019).

Visit our community

Trying to conceive? Discuss ovulation, sex positions for getting pregnant and more in our friendly community.

• Find out how polycystic ovary syndrome (PCOS) could affect ovulation.
• Taking longer than you expected to get pregnant? Learn the most common causes of infertility.
• What you need to know about giving up contraception.