Medically reviewed by Sophia Yen, MD, MPH – Written by Varuska Patni. Updated on May 10, 2021
TLDR: Technically, yes but it’s very unlikely.
For those not trying to get pregnant, a period can be a nuisance or a bearer of great news (that you’re not pregnant). But don’t go running to have unprotected sex now that it’s here. You can still get pregnant while on your period, even if the risk is very low.
What is the Fertility Window?
A period marks the beginning of a new menstrual cycle and based on the 28-day average cycle model, you should ovulate about 14 days after the start of your period. Ovulation occurs when your ovary pops out an egg.
You are most likely to get pregnant 12-24 hours after an egg is released by your ovary. However, each person’s fertility window may differ, and the 28-day cycle may not apply to you. If you have irregular periods, it may be more difficult to determine when you are likely to get pregnant.
Some individuals use the fertility awareness method (FAM) (similar to the Catholics’ rhythm method) as their only form of birth control. This method takes into account factors indicative of ovulation, such as checking your temperature every morning and looking at your cervical mucus more often. However, FAM is among the least effective forms of birth control with a 24% chance of leading to pregnancy.
On which days are you less likely to get pregnant?
All this uncertainty can make it difficult to determine when you’re in the clear from getting pregnant. During a menstrual period, the endometrium (a.k.a lining of the uterus) breaks down, thus, decreasing your risk of getting pregnant due to the lack of space for a fertilized egg to stick.
With all of that being said, it is possible to get pregnant during this time. If you have unprotected sex on the last days of your period, your risk of pregnancy may be higher. Sperm can live in the uterus for up to five days, so it could still attract an egg once the fertility window restarts after your period ends.
Having Sex on your Period
Sex while on your period can be a messy undertaking. However, if you and your partner are comfortable, you are more than welcome to go for it. Sex may even help with unpleasant period symptoms, like camps.
If you are having heterosexual, penetrative sex, you should use an external barrier (i.e. condoms) to prevent even the small risk of pregnancy. Our CEO and co-founder, Dr. Sophia Yen, says “Always use a condom plus a hormonal contraception or the copper IUD if you really want to have a very low chance of pregnancy.” If nothing else, the condom will protect both partners from Sexually Transmitted Infections (STIs).
While a period is usually a sign of not being pregnant, you could be mistaking other forms of bleeding for your period (which means you might actually be pregnant). Implantation bleeding is a type of bleeding that occurs one or two weeks after fertilization (when an egg and sperm link). It is thought to be the result of an embryo making its way into the uterus, causing the blood vessels to burst. Although implantation bleeding may be tricky to detect, a common sign is an irregular bleed that is lighter or different in color compared to your normal period. This does not necessarily indicate pregnancy, but it is always a best practice to take a test if you think there could be any risk.
Breakthrough bleeding, or spotting is bleeding that occurs between periods. In many cases, this is harmless and simply the result of a change in hormones. For instance, breakthrough bleeding may occur if you recently started or switched your hormonal birth control. Thankfully, this bleed typically only lasts for about a week (or even less in some cases). That being said, if you are bleeding for an extended period of time while taking birth control, consult a doctor to make rule out additional health conditions.
What’s the takeaway?
Your chance of getting pregnant while on your period is very low, BUT still very possible. Furthermore, if your goal is to not get pregnant, using condoms and/or taking hormonal birth control is your best bet. Both methods block sperm from attaching to eggs in the uterus thus, preventing fertilization.
TLDR: Using multiple forms of birth control (condoms + one form of hormonal birth control, NOT two types of hormonal birth control) decreases your risk of becoming pregnant.
How can Pandia Health help?
If you’re running low on birth control and don’t want to go to the pharmacy because you have #BetterThingsToDo, make sure to sign up to get automatic refills and FREE delivery of birth control pills. We also write prescriptions for individuals who live in AZ, CA, CO, FL, IL, MI, NV, GA, WA, & WY. Schedule a virtual consultation with one of our expert doctors so we can help find something that works for your lifestyle. With Pandia Health, you can feel confident that you will never run out of birth control.
Frequently Asked Questions
Can you get pregnant during your period?
It is possible to get pregnant during your period because the sperm may be present nearby – it can live in the uterus for several days. If you plan to have sex during this time, it is always a best practice to use a condom and/or take hormonal birth control (if you’re already on the pill, take it as usual).
Can you get pregnant right before your period?
The chance of getting pregnant before your period is very low, but still possible. Females with a regular 28 to 30-day menstrual cycle often have their ovulation happen between the eleventh and twenty-first day. The egg is usually only available for conception within a 12-24 hour period. Furthermore, the days leading up to your period are actually the safest to engage in sexual intercourse without the expectation of pregnancy (if you use condoms, you can have sex anytime).
Can you get pregnant on the first day of your period?
Getting pregnant on the first day of your period is unlikely, but possible. If you have an irregular or shorter menstrual cycle, ovulation may occur closer to the first day of your period. If an egg is pregnant during this time and you have unprotected sex, you could get pregnant.
Disclaimer: This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis or treatment. It should not be relied upon for specific medical advice. Please consult your doctor or healthcare provider before changing, stopping, or starting any medications.