Can you get pregnant on your period?

This article is also available in Spanish and Swedish

Can you get pregnant on your period?

Most people cannot get pregnant if they have sex on their period, this is because there is only a short window in the cycle when conception is possible. For most people with a regular cycle, this fertile window won’t open until the days after your period has stopped.

There’s another biological reason why conception on your period is unlikely, and that’s because the conditions aren’t right for the implantation of a fertilized egg cell. Each cycle, your uterus lining sheds and rebuilds again. Your period is what happens when you’re shedding this womb lining, which is needed to support the growth of the egg cell. While this means conception can’t happen when you’re on your period, that doesn’t mean you can’t get pregnant if you have sex on your period. This is because of sperm survival…

Sperm cells can live in the female reproductive system for up to five days. It is possible (although very rare) for them to survive until ovulation if you have sex at the end of your period and then ovulate early. That said, if you have a regular menstrual cycle (between 21 and 35 days in length), this is extremely unlikely to happen to you.But if you have very short cycles (for example, a cycle that’s 20 days long), and a longer period (that lasts around a week), there is a risk of pregnancy. 

If you’re planning pregnancy, you’re very unlikely to be fertile on your period, and the chances of conceiving are extremely low at this time. Finding your fertile window instead can help you get pregnant faster.

Keep in mind many of us will find that our menstrual cycles vary throughout our fertile years, and can be impacted by factors such as stress and changes to diet. Many women also find they have shorter menstrual cycles as they get older. 

Can you get pregnant on the last day of your period?

Again, this is only possible if you have a longer period and a very short cycle. Most women are not fertile while they’re on their periods, although if you are in the minority of people with very short cycles and longer periods, the end of your period is the time when you may be at risk of becoming pregnant. 

If you’ve had unprotected sex in the last five days and are worried you might be pregnant, you can take emergency birth control to protect yourself from unintended pregnancy. 

Can you get pregnant right after your period?

Again, it’s possible, but it’s unlikely that you’ll get pregnant straight after the end of your period. For most people, the fertile window won’t start for several days to a week after they’ve stopped bleeding. 

The fertile window is defined as the five days before ovulation, when sperm can survive within the fallopian tubes, and the day of ovulation itself (when the egg cell can survive for a maximum of 24 hours). While you may have a few days of buffer after your period ends before you become fertile, if you’re not familiar with your own cycle, this is a risky time to be having sex, as ovulation can happen earlier than expected (even for those with regular cycles).

Can you get pregnant right before your period?

After ovulation, the female egg cell can only survive for a maximum of 24 hours. Since ovulation tends to happen around the middle of your cycle, this means you’re not fertile in the days right before your period.

However, ovulation can be tricky to confirm without the right tools or knowledge, and there is a risk your ovulation day may move and make your cycle longer than usual. If this happens, and you assume you’ve ovulated, and then have unprotected sex, but then ovulate later than expected, there is a risk you could get pregnant. 

Getting to know your cycle is a great way to remove the guesswork and is a natural way to prevent pregnancy if you avoid unprotected sex on fertile days.

Can you get pregnant while using birth control?

The bleeding you have on hormonal birth control isn’t technically a period but is known as a withdrawal bleed. And yes, you can still get pregnant if you have sex while you’re on birth control. This can happen if the method fails or (more commonly) if you use your birth control method differently from how it’s intended to be used, for example forgetting to take a pill one day. This is considered ‘typical use’ effectiveness. The pill is 93% effective with typical use, meaning seven women out of a hundred will get pregnant using it over the course of a year. When used perfectly, the pill is more than 99% effective at preventing pregnancy.

No birth control method is 100% effective, but some require less work than others, which can lead to higher typical use effectiveness ratings. For example, your chance of getting pregnant with an IUD is less than 1%. 

There are many things to consider when choosing a birth control method, including its effectiveness, and whether that method suits you and your routine.

Take control of your fertility today 

Natural Cycles is a temperature-based birth control method that’s based on the science of your cycle. The algorithm learns the pattern of your unique cycle to detect small but significant shifts in temperature, by doing this it can confirm and predict ovulation, so you know where you are in your cycle and whether or not you’re fertile that day. 

Non-hormonal and non-invasive, Natural Cycles is the first app of its kind to be FDA Cleared. It’s 93% effective with typical use, and 98% effective with perfect use. Why not find out if it could work for you today?