Trying to conceive but got my period

Yes, it's possible to get pregnant right after, on, or even just before your period. The likelihood of getting pregnant varies depending on timing and the length of your cycle.

If you're trying to get pregnant, the best time to have sex is just before or during ovulation. If you're not trying to get pregnant, use reliable contraception no matter which day of your cycle it is.

Here's a rundown of your chances of getting pregnant during your period, and on the days before and after it.

Can you get pregnant on your period?

Yes, but it's unlikely. It's possible to get pregnant during your period when:

• You have a very short menstrual cycle (the time from the first day of one period to the first day of your next period).
• You have long periods.
• You were bleeding around the time of ovulation (spotting between periods) and mistakenly thought it was a regular period. If you had unprotected sex at that time, you could conceive.

Here's why you could get pregnant during your period:

Ovulation happens during the middle of your menstrual cycle – anywhere between 7 and 19 days before your period starts. During ovulation, an egg reaches maturity in one of your two ovaries, the ovary releases the egg into your abdomen, and it gets sucked into the nearest fallopian tube, where it can survive for about 24 hours. Conception occurs when an egg and sperm meet in a fallopian tube.

A typical menstrual cycle is 28 days, which usually leaves a good few days between the end of your period and the start of ovulation. But some women have cycles as short as 22 days. If you have a short cycle or long periods, you could ovulate right after your period ends. And because sperm can survive in your reproductive tract for up to five days, if you have sex during your period, it's possible that live sperm will be there when you ovulate, ready to fertilize the egg.

Can you get pregnant right after your period?

Yes. Immediately after your period is still not the ideal time to get pregnant, but you are more likely to conceive at this time than during your period. That's because you're closer to the time when you will ovulate.

Again, two factors can increase your chances of getting pregnant right after your period:

1. A short menstrual cycle
2. A long period

The shorter your cycle and the longer your period, the more likely it is that you'll be fertile during the last few days of your period or in the days just afterward.

Can you get pregnant right before your period?

Yes, but it's unlikely, and chances are even lower that you could conceive during this time than while you are on your period or right after it.  That's because the time you are fertile has probably passed.

However, if you have a menstrual cycle that is shorter than the typical 28 days, there are fewer days between ovulation and the start of your next period during which you are not fertile. That means your chances of getting pregnant right before your period are higher if you have a shorter cycle and lower if you have a longer cycle.

Learn more:

• The best time to get pregnant
• How to get pregnant: A primer
• Ovulation symptoms
• Ovulation predictor kits

What is the menstrual cycle?

The menstrual cycle is what your body goes through to get ready for pregnancy. This cycle is the time from the first day of your period (first day of bleeding) up to the day before the start of your next period. 

Ovulation usually happens during the second half of the cycle. This is when an egg is released from one of your ovaries. To get pregnant, the egg needs to be fertilised by the sperm.

Ovulation doesn’t happen every month for every woman. There are some conditions that may interfere with ovulation, such as endometriosis and polycystic ovarian syndrome (PCOS). If you are not getting a monthly period and are trying to get pregnant, speak to your doctor.

How long is the menstrual cycle?

Women’s cycles can vary in length and from month to month, but the average is around 28 days. It’s normal to have regular cycles that are longer or shorter than this (from 21 to 41 days).

It doesn’t matter how long your cycle is, most women will ovulate around 10 to 16 days before the start of their next menstrual cycle.

Can I get pregnant at any time during my cycle?

Yes, but it’s unlikely you’ll get pregnant just before or just after your period. You are most fertile when you ovulate, so this is when you’re most likely to get pregnant. Understanding your cycle and knowing more about what is happening month during the month, can help you learn the best days to get pregnant.

Find out more about ovulation and fertility, including top tips for finding your fertility window. You can also use our ovulation calculator to find out more.

What if my cycle is irregular?

It can be more difficult to get pregnant if you have irregular periods because you may not ovulate regularly.

There are many possible causes of irregular periods, which may affect your fertility. For example:

• extreme weight loss or gain
• stress or exercising too much
• medical conditions such as thyroid problems or polycystic ovary syndrome.

Having irregular periods does not mean you won’t get pregnant and there are things you can do to boost your chances of success.

See your GP if your periods have stopped, you’re missing monthly periods or you have irregular periods and are struggling to get pregnant.

I’ve been using contraception. Will this affect my cycle?

This depends on what type of contraception you’ve been using. If you’ve been taking the pill, your period may be irregular when you first come off it, so try to give yourself up to 3 months for your natural menstrual cycle to get back to its ‘normal routine’.

The first period after stopping the pill is known as a ‘withdrawal bleed’. The next one after this is your first natural period.

The contraceptive injection can also affect your cycle. Your periods may change and become irregular, heavier, shorter, lighter or stop altogether. This can carry on for some months after you stop the injections.

If you use the contraceptive implant your fertility will return to normal as soon as it is taken out.

How soon can I get pregnant after coming off the pill?

You can get pregnant as soon as you come off the pill but if you’re trying to get pregnant, it’s a good idea to wait until you’ve had a natural period. This will give your body time to adjust and give you a chance to make sure you’re ready for pregnancy. Make use of our pregnancy planning tool to see what else you can do.

My menstrual cycle is still irregular. Has the pill affected my fertility?

It’s unlikely the pill has caused any fertility problems, but it can sometimes cover up problems you already have, such as missing periods or PCOS .This is because the pill prevents the ovaries from releasing an egg (ovulation), so although it’s normal to experience period-type bleeding on the pill, you don’t have a ‘real’ period.

Contact your GP if you’re still having irregular periods 3 months after stopping contraception.

Can I use my menstrual cycle to predict my due date?

Yes. You can work out how far along your pregnancy is (and therefore when the baby is due) by counting from the first day of your last period.

This can be confusing because you probably didn’t get pregnant until around 2 weeks later, after you ovulated. Even if do you know the date you got pregnant, this is counted as day 14 of your pregnancy (if your cycle is 28 days), not day 1.

Your pregnancy is calculated from your last menstrual period because every time you have a period this is the body’s way of getting ready for pregnancy. It also gives healthcare professionals a standard to follow because it’s very difficult to know exactly when the sperm fertilised the egg.

If your period is irregular or if you’ve recently been on the pill it will be harder to try and work out your due date.

The most accurate way to work out your due date is to have an ultrasound scan when you’re around 11 to 14 weeks pregnant. This is used to see how for along you are and check your baby’s development.

I’m pregnant but have some bleeding. Is this my period?

Implantation bleeding sometimes happens in pregnant women around the time their period would have been due. Implantation is when the developing embryo plants itself in the wall of your womb. An implantation bleed is very light bleeding (spotting) that is usually pinkish and sometimes brown. Not everyone will have an implantation bleed.

It’s common to have light bleeding or ‘spotting’ without pain before 12 weeks. This isn’t often serious, but you should contact your doctor, midwife or Early Pregnancy Unit immediately to be checked, just in case.

Find out more about bleeding in pregnancy.

Can you still get your period after trying to conceive?

Why am I getting early periods when trying to conceive?