Can you get pregnant having sex on your period?

22nd January, 2021 • 5 min read

There are many misunderstandings about when you can and can’t get pregnant. Many people think you can’t get pregnant if you have sex while you’re on your period – but this isn’t true. It’s unlikely that you’ll get pregnant this way, but it’s not impossible.

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Read on to learn why this is, and what you can do if you don’t – or do – want to get pregnant.

How is it possible to get pregnant on your period?

If you have unprotected sex (sex without using contraception), you can get pregnant at any point during your monthly menstrual cycle. In other words, there’s never a time when there’s no chance of getting pregnant from having sex – even if you’re on your period.

Day 1 of your menstrual cycle is counted as the day your period begins, and the cycle then continues until the first day of your next period. You’re most likely to get pregnant when an egg gets released from your ovaries – this is called ovulation, and it’s when you’re most fertile. This usually happens around the middle of your cycle, 12 to 14 days before the start of your next period.

So it’s unlikely that you’ll get pregnant after having sex on your period, because an egg hasn’t been released. But it’s possible. This is because sperm can survive in the body for up to 7 days – so if you ovulate early in your cycle (and some people have naturally short cycles), you could still get pregnant.

How ovulation works

Once a month, ovulation happens when a tiny egg is released from one one of your ovaries. In rare cases, more than one egg makes its way out, usually within a day of the first egg being released.

At this time, changes also happen in your womb and cervix (the part of the womb that leads to your vagina) to help you get pregnant. The lining of the womb gets thicker, to hold a fertilised egg, and the mucus in the cervix gets thinner, to allow any sperm to swim more easily.

The egg travels slowly towards your womb, down a tube called the fallopian tube. If it meets sperm, it can be fertilised, and will then be implanted in the thickened womb lining. If the egg isn’t fertilised, it comes out of your body through your vagina during your period, along with the womb lining.

What to do if you don’t want to get pregnant

Some people try to avoid getting pregnant by studying their menstrual cycle and working out when they ovulate. But it’s difficult to know when ovulation happens, and it can change each month. And as we know, it’s possible to get pregnant at any time during your cycle.

If you’re trying to avoid pregnancy, an effective method is to use

during sex – such as condoms, which not only protect you from pregnancy, but also from sexually transmitted infections.

There are also several effective long-acting, reversible methods of contraception. These include an injection, implant and an intrauterine system or device (IUD). An

is a small device made from plastic and copper that fits inside your womb. It stops sperm from reaching an egg, and can also stop a fertilised egg from being implanted in the womb lining.

Finally, there is

emergency contraception
, which can be used after having unprotected sex, or if another method of contraception hasn’t worked. There are 2 types of pill you can take – often referred to as the ‘morning-after pill’ – or an IUD can be used.

You can find more information about avoiding pregnancy


What to do if you want to get pregnant

If, on the other hand, you want to get pregnant, there are things you can do to increase your chances.

First, try to get to know your menstrual cycle and when you ovulate – this is your ‘fertility window’, when you’re most likely to get pregnant if you have sex, and is usually 12 to 16 days after your last period started. As discussed, it can be difficult to pinpoint ovulation, but there are apps and ovulation kits that may help. Advice is to have regular sex, every 2 to 3 days.

It’s also a good idea to stay as healthy as possible when trying to get pregnant. Try to eat a balanced diet and exercise regularly, and avoid too much alcohol, smoking and stress if possible.

Most importantly, you’ll want to speak to your doctor about what you should and shouldn’t do when you’re trying to get pregnant.

Key points

  • you can get pregnant after having sex at any point during your menstrual cycle, even if you’re on your period
  • you’re most fertile during ovulation, which usually happens around the middle of your cycle
  • there are several methods of contraception that can help you avoid getting pregnant
  • there are also things you can do to increase your chances of getting pregnant

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.