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When am I most fertile during my cycle?

You're most fertile when an egg is released from your ovaries (ovulation). However, for the best chance of getting pregnant, have sex every two to three days throughout the month.

Regular sex

Although you're most fertile during the days around ovulation, you don't need to plan having unprotected sex around when you're ovulating if you're trying to conceive.

Trying to plan sex around the time you're ovulating can be stressful. If you're stressed, you're less likely to have sex as often, which can affect your chances of getting pregnant.

Your menstrual cycle

Knowing the length of your menstrual cycle can help you work out when you’re ovulating.

Your menstrual cycle lasts from the first day of your period up to, but not including, the first day of your next period. The length of a woman's menstrual cycle can vary. Anything from 24 to 35 days is common, although it could be longer or shorter than this. On average, it lasts 28 days.

Ovulation

During your menstrual cycle, hormones are released to stimulate your ovaries. An egg stored in your ovaries begins to grow and mature. When the egg is mature, it's released from your ovaries (ovulation) and travels down the fallopian tubes. Occasionally, more than one egg is released.

Ovulation occurs roughly halfway through your menstrual cycle, usually around 10 to 16 days before the start of your next period. If your menstrual cycle is 28 days long, this would be around days 13 to 19 of your menstrual cycle.

Some women may recognise signs that they're ovulating, such as:

  • a change in vaginal secretions, so they become thinner and more stretchy
  • change in body temperature

Other signs such as breast tenderness, bloating, mild abdominal pain and increased sex drive are less reliable.

For more information, see How can I tell when I'm ovulating?

Some women choose to buy special ovulation prediction kits, which test your temperature or hormone levels to find out when you're ovulating.

If you don't notice any signs of ovulation or your periods are irregular, you should contact your doctor.

Read the answers to more questions about pregnancy.

Further information:

Menstrual cycle: animation

This animation explains in detail how the menstrual cycle works.

Media last reviewed: 21/02/2025

Next review due: 21/02/2025

Page last reviewed: 20/05/2024

Next review due: 19/05/2024