Busting the myth – Can you get pregnant on your period?

We’re sure we can vouch for all girls when we say, at some stage in our life we’ve all been told that ‘you can’t get pregnant on your period’. For many years, we weren’t sure if there was any truth behind this, or if it was just complete rubbish – and so we’re settling it here for once and for all.

So after a lot of research, and many many discussions with people who know their sh*t, we can, in fact, confirm that this myth has been busted – you can actually get pregnant while on your period!

Can you get pregnant on your period?

Although the chances of getting pregnant whilst on your period are very slim, there is a still a chance that this could happen if you are having unprotected sex, even during or just after your period. It is also possible to get pregnant if you have never had sex before, during your first period. Remember, there is no 100% safe zone of the month where you can have sex without contraception and not risk becoming pregnant. However there are times in your menstrual cycle when you’re at your most fertile and this is when you’re most likely to conceive.

To fully understand the chances and how this can happen, first you’ll need to be able to understand how your menstrual cycle works.

So let us explain…

  • Your cycle starts on the first day of your period, and lasts until the first day of your next period
  • About 10 to 16 days before the start of your period, you will ovulate (when one of your ovaries releases an egg – because you have two they take it in turns each month)
  • Once you’ve ovulated, you enter the Luteal phase, when the now empty follicle develops the corpus leteum, which produces the hormone progesterone
  • The lining on your uterus thickens in preparation for a fertilised egg to implant
  • If you have not conceived, then the egg passes into the uterus, hormones levels drop, and the womb lining sheds as you begin your next period

The actual statistics for how likely you are to get pregnant whilst on your period depends on a variety of factors including:

  • Whether you used contraception or not
  • The length of your menstrual cycle
  • The length of your period
  • When you had sex

You are most fertile when you are ovulating. A typical menstrual cycle lasts between 28 and 30 days, so you are usually fertile between days 11 and 21, although of course this can vary from female to female. If your period lasts 5-7 days and you have sex towards the end, you may be able to conceive on day 11, as although the egg only lives for 12-24 hours after being released, you can get pregnant even if you have sex days before you ovulate, as sperm can survive up to 5 days after intercourse – (who knew!)

You can also conceive after having sex during your period if you have short menstrual cycles, as this means you ovulate a few days earlier, and closer to the end of your period.

Can I get pregnant during my period on birth control?

In short, no. If you are taking birth control correctly and consistently, then you should be protected against pregnancy all the time, which includes either the seven day break or the days you take your placebo pills. You can still have sex during this week without getting pregnant, as long as you’re taking the pill correctly and starting every new pack correctly.

Can I get pregnant just before my period?

The probability of conceiving if you have sex a couple of days before your period is very slim. As your egg lives for around 12 – 24 hours after it is released, this means your fertility window closes soon after you ovulate, however there is still a chance.

How many days after my period can I get pregnant?

Again, although unlikely, it is still possible as no matter what time of the month, there is always a risk of pregnancy if you have sex without contraception. If you ovulate early – when you have short menstrual cycles – you may be able to get pregnant at this time of the month. However, once you’ve finished your period you move into your fertility window, which means your chances of getting pregnant increase as you approach ovulation.

Can I get pregnant during your first period after birth?

It is in fact possible to get pregnant less than 6 weeks after having a baby, although very unlikely. However, it is impossible to get pregnant until a female ovulates again. The point at which ovulation happens varies from female to female, which means some females can get pregnant earlier than others. Sometimes ovulation happens before a period, so it is also possible for a woman to get pregnant before having the first postpartum period.

Does tracking your cycle really help?

There are various tracking apps around, however a firm favorite of The Lowdown is Natural Cycles app. The Natural Cycles app contains an algorithm that analyses your temperature (measured using a thermometer) and menstrual cycle data to calculate when you are fertile, and telling you to avoid sex or use other protection on your fertile days. Unlike other fertility awareness methods, it tries to minimise human error as the algorithm does the calculations and interpretations. This app is really handy to let you know when you’re ovulating (when you’re more fertile) as well as when to expect your period.

This guide was brought to you by The Lowdown. We are the world’s first contraception review platform, providing real-life experiences from thousands of reviews collected from our community of men and women.

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