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Can You Get Pregnant while on Your Period? Chances to Conceive During Menstruation

Despite a popular belief, you still need to use birth control to have sex while being on period. This is because you can’t exactly predict when your ovulation will occur.

girl with a period calendar

Can you get pregnant while on your period?

The chances of getting pregnant on period are very low, but the probabilities are there.

Becoming pregnant on period is unlikely for most of the women, but it is not something which is impossible. The answer lies in thoroughly understanding a female’s fertile window. When on period, is usually not the time to have sex if you are trying to get pregnant. Becoming pregnant depends on the occurrence of ovulation in your cycle. The ovulation day varies from one woman to another and in the same woman from cycle to cycle.

Apart from being less desirable and messier, having intercourse during your monthly period will more than likely not result in pregnancy. You can conceive from having sex while being on period if you happen to ovulate early in your cycle, or if your monthly periods last much longer than the average 5 days. 

The issue of your chances of getting pregnant while on period does not have a specific answer. However, exceptions are always there. If any woman has a shorter monthly cycle, there are chances of her getting pregnant while having sexual intercourse during her period. If your monthly cycle is shorter (e.g. 21-24 days) this means your ovulation occurs early in the cycle. Sperms can reside for two, three and up to five days inside you. You could have sexual intercourse towards the end of your monthly cycle and then get pregnant four or five days later with your early ovulation.

Most females do not ovulate on day 14. In fact, only 30 percent of females have cycles where the day of ovulation falls entirely within the days recognized by clinical guidelines.

The earlier your ovulation occurs, the earlier you will get your day of fertility since your fertile window starts 5 days before your ovulation begins. If your ovulation occurs on day fourteen of your cycle, then your fertile window starts on day 9. But if you ovulate on day 8 of your cycle, your fertile window begins on day 3 — right in the middle of your monthly period. One thing to keep in mind is that all days of high fertility are not designed equal. The days closer to the day you ovulate carry increased chances of pregnancy as compared to the ones further from ovulation. 

Sexual intercourse just a day before your ovulation, in the best-case scenario, results in about 30% chance of pregnancy. Having sex 5 days before the day of ovulation has a lower than 5 percent chance of pregnancy. This means that even if ovulation occurs early enough in your monthly cycle for your fertile window to start in the ending days of your period, your possibilities of becoming pregnant on these days are not very high.

looking at the pregnancy test.

Can you get pregnant right before your period?

The chances of getting pregnant right before your monthly period are extremely low. For females having a typical cycle of twenty-eight to thirty days or longer and cycles being regular, it is safe to say that you ovulate between day eleven and day twenty-one. The eggs are only available for 12 to 24 hours for getting pregnant.  

You can basically say that the days before your monthly period are the safest for having sexual intercourse without the risk of becoming pregnant. The number of “safe days” right before your monthly period is higher with longer cycles and shorter with shorter monthly cycles.

If you know exactly when your ovulation happened and you wait for thirty-six to forty hours later, then you definitely are beyond the likeliness of pregnancy. The further you move away from your day of ovulation, the likeliness for you becoming pregnant is very less. This is not the right time to have sex if you are making attempts to become pregnant. 

Can I get pregnant the day before my period and still have a normal period? 

This is a question often asked by Flo users. And the answer comes from a misconception that a woman can’t get pregnant during her period.

Some women experience spotting during ovulation and consider it period blood when it’s exactly the other way round — the woman is very fertile during these days. And having unprotected sex when you experience ovulation spotting can absolutely result in pregnancy.

Another, although very rare case, is when ovulation happens before the end of your period or just a few days after the period ends. If you have unprotected sex during period and have ovulation just a couple of days afterwards due to irregular cycle, you can get pregnant. 

Remember — sperm can live in your body for up to 5 days, so you can get pregnant if you had sex the day before your period and still had a normal period or spotting.

Can you get pregnant right after your period?

Yes, you can conceive right after your monthly period. After your monthly periods are finished, you begin to move into your fertile window. In a typical cycle that happens every 28 to 30 days, the days when your fertility is high is usually between day 11 and day 21.  Sperms can reside two, three and up to five days. If your monthly period lasts for five to seven days, and you have sexual intercourse right after that, you are entering into your fertile window. 

If the bleeding stops on day six, have intercourse on day seven, and ovulate on day 11. The sperm from day six will be residing in the fallopian tubes for the pregnancy to happen. Of course, the possibility of you getting pregnant right after your periods increases with every passing day after your period bleeding has stopped. 

If you are trying to become pregnant, this is the right time to start having sex. Having sexual intercourse every other day for the next 14 days increases your chances of conception.

Best time to get pregnant after period

You are most likely to become pregnant if you go for sexual intercourse during the 2 days before your ovulation begins, or exactly on the day you ovulate – when an egg is released from your ovary. This happens usually about 2 weeks prior to the start of your next monthly period, but it varies, so if you want to conceive, try one of the efficient methods of predicting ovulation.

Here are the top 4 methods for predicting your ovulation in order to find out the best time to get pregnant after period:

  1. If your monthly cycle has the same number of days every time, make use of an ovulation calculator to find out when you are most fertile each month. 
  2. Another method to get an idea of when you can become pregnant is tracking the signs and symptoms of ovulation, like changes in your body temperature and cervical mucus. This is the best time to get pregnant after period.
  3. Use ovulation predictor kits.
  4. Install Flo and predict your fertile days using our AI-enhanced algorithms.

Can you have a period and still be pregnant?

No, it is usually not possible to bleed while being pregnant. Once your body starts releasing the pregnancy hormone called hCG (human chorionic gonadotropin), your monthly periods will stop. However, you may have conceived and experience light bleeding at about the same time your monthly periods would have been due. It’s called implantation bleeding.

If you’re pregnant and experience bleeding or spotting, please contact your healthcare provider. 

Birth control to prevent getting pregnant on your period

The risk of pregnancy is there even when you go for sex while being on period. To avoid pregnancy, it is important to start taking long-term contraception.

Birth control methods for prevention of pregnancy on your period include:

  • a male condom
  • a combined oral contraceptive pill
  • progestogen-only  pill (mini-pill)
  • the contraceptive patch
  • long-acting reversible contraception, like the implant or intrauterine device (IUD)
Arévalo, M., Sinai, I., & Jennings, V. (1999). A fixed formula to define the fertile window of the menstrual cycle as the basis of a simple method of natural family planning. Contraception, 60(6), 357-360.
Blake, K. R., Dixson, B. J., O'dean, S. M., & Denson, T. F. (2016). Standardized protocols for characterizing women's fertility: A data-driven approach. Hormones and behavior, 81, 74-83.
Dunson, D. B., Colombo, B., & Baird, D. D. (2002). Changes with age in the level and duration of fertility in the menstrual cycle. Human reproduction, 17(5), 1399-1403.
Dunson, D. B., Baird, D. D., Wilcox, A. J., & Weinberg, C. R. (1999). Day-specific probabilities of clinical pregnancy based on two studies with imperfect measures of ovulation. Human Reproduction, 14(7), 1835-1839.
Sohda, S., Suzuki, K., & Igari, I. (2017). Relationship Between the Menstrual Cycle and Timing of Ovulation Revealed by New Protocols: Analysis of Data from a Self-Tracking Health App. Journal of medical Internet research, 19(11).
Stanford, J. B., White Jr, G. L., & Hatasaka, H. (2002). Timing intercourse to achieve pregnancy: current evidence. Obstetrics & Gynecology, 100(6), 1333-1341.
Wilcox, A. J., Weinberg, C. R., & Baird, D. D. (1995). Timing of sexual intercourse in relation to ovulation—effects on the probability of conception, survival of the pregnancy, and sex of the baby. New England Journal of Medicine, 333(23), 1517-1521.
Wilcox, A. J., Dunson, D., & Baird, D. D. (2000). The timing of the “fertile window” in the menstrual cycle: day specific estimates from a prospective study. Bmj, 321(7271), 1259-1262.

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  • Amazing! Ricecake2003
    This app is super useful for tracking periods, and has given me mostly accurate predictions so far! I especially love that you can comment anonymously on posts and get help from and give help to the community.
  • Such an intuitive app! Hannah Malone
    I've tried several period tracker apps on the market and nothing is as good as Flo. It's accurate, detailed providing you with an abundance of parameters to log, and they even provide useful articles and surveys to help you better understand the complex nature of the female body.

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