How conception works

For the best chance of getting pregnant, you need to get your fertile eggs and your partner's sperm together as often as possible.

How the menstrual cycle works

  1. Your cycle starts on the first day of your period and continues up to the first day of your next period.
  2. At the same time, eggs begin to mature in the ovary.
  3. The lining of the womb starts to thicken in readiness for fertilisation.
  4. During ovulation your cervical mucus becomes thinner and clearer to help the sperm to reach the released egg.
  5. About 10 to 16 days before the start of your next period, an egg is released from one of the ovaries (ovulation).
  6. If sperm is present at the moment of ovulation, or some time during the next 24 hours, the egg may be fertilised.
  7. If the egg has not been fertilised, the egg is re-absorbed by the body, the hormone levels drop, and the womb lining is shed – the beginning of your next period.

Now that you know all about your menstrual cycle, read our top tips for getting ready to conceive.

Have more sex!

The best thing to do to boost your chance of conceiving is to have regular sex throughout your cycle.

Time sex right

To boost your chances of conceiving, aim to have regular sex throughout your cycle so you know that there should hopefully be good-quality sperm waiting when the egg is released. An active sex life is all most people need to conceive.

If you are quite sure when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. Continue having sex during ovulation. After this your fertile time will be over for that cycle.

When does ovulation happen?

Ovulation usually happens about 10 to 16 days before the start of your next period, so  it helps to know your cycle length before you start trying to conceive.

You may never have considered when you might ovulate within your cycle, and if you have been using a hormone contraceptive such as the Pill, you won’t have had a natural menstrual cycle for a while.

As a first step, mark on your diary the dates that you bleed during a period. You can then count how many days from the first day of your period to your next period to work out the length of your cycle.

There are also apps available that can help you monitor your cycle.

Cervical mucus changes

The cervix secretes mucus throughout the menstrual cycle, starting off sticky white and gradually becoming thinner and clearer.

Before and during ovulation the mucus increases and becomes much thinner, slippery and stretchy. Women often compare it to raw egg white.

This thinner mucus is designed to help the sperm swim easily through it. It indicates that you are in your fertile phase, so this is the time to have sex if you want to get pregnant, but use contraception if you do not!

The last day you notice the wetter secretions is sometimes known as ‘peak day’ and for most women this occurs very close to the time of ovulation.

Temperature

You can also find out about your menstrual cycle by keeping a note of your temperature each morning when you wake up. Your temperature rises by about 0.2°C when ovulation has taken place.

As it is only an indicator that you have ovulated, and doesn’t tell you when your fertile time starts, this is not very useful for most women.

Using ovulation predictor kits (OPK)

Ovulation predictor kits are available from chemists and are fairly simple to use. They work by detecting a hormone in your urine that increases when ovulation is about to take place.

The simplest urine kit tests for luteinising hormone (LH), which surges 24-36 hours before ovulation. This will help to identify the best two days for conception, although a woman can be fertile for a day or so before and after this time.

It is best to become familiar with your usual menstrual cycle to help figure out when you should start testing. If you have an irregular cycle then an ovulation predictor kit can help you identify the time of ovulation, but expect to use more of the test strips.

Find out more in our conception FAQs

Read more

  • Woman stretching.

    The benefits of exercise for conception

    Being fit and healthy is an advantage if you're thinking about starting or adding to your family.

  • How will I know when I am pregnant?

    How do you know when you're pregnant? If you've been trying for a baby, there are a few ways to find out whether you're expecting.

  • Happy couple laughing.

    Are you ready to conceive?

    Follow these simple steps to make sure that your body is in the best condition for conception. If you have stopped using contraception you could be pregnant at any time.

  • Happy dad with baby

    Male fertility

    It takes two to make a baby. We’ve put together some useful tips for making super sperm and giving you the best chance of making a healthy baby.

  • Happy couple.

    Top tips for conception

    If you've decided you're ready to start a family, find out more about getting your pregnancy off to the best start.

Sources

  1. Macdonald S, Macgill-Cuerden J (2012) Mayes’ midwifery: a textbook for midwives, 14th edition, London Balliere Tindall
Hide details

Last reviewed on June 13th, 2017. Next review date June 13th, 2020.

Was this information useful?

Yes No

Comments

Your comment

Add new comment