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Late period or pregnant after morning-after pill?

by Dr. Tessa Commers
Julie Medical Advisor
Morning After PillAfter Sex

If you’ve taken Julie or another morning-after pill and your period is late, you might be wondering: is this a side effect or am I pregnant? This is a super common question after taking Julie and there are a few different things that could be going on. Read on to learn more about delayed periods after taking Julie.

Does the Morning-After Pill Affect Your Period?

The morning-after pill, like Julie, can temporarily affect your period. In fact, changes to your cycle is one of the most common reported side effects of the morning-after pill. That’s because it contains a higher dose of levonorgestrel (the main ingredient in Julie) compared to what’s found in birth control pills, so it’s likely to impact your body’s natural hormone levels for a short period of time. Waiting for your period to arrive can be stressful, especially after taking emergency contraception, but just know that it’s totally normal for your period to be delayed.

Your period might also be lighter or heavier than usual, or you could experience spotting in between cycles. Since factors like stress can also affect your menstrual cycle, this could make your period even later. If your period is more than 1 week late, it’s best to take a pregnancy test.

How Julie (the morning-after pill) might affect your period

Taking the emergency contraceptive levonorgestrel, aka Julie or Plan B, can cause symptoms like spotting (irregular bleeding between periods), a heavier or lighter menstrual flow, a shorter or longer period, or an early or delayed period. These side effects are common and shouldn’t last beyond one menstrual cycle. However, if you are still experiencing irregular bleeding after a month, or your period is more than a week late, it’s recommended you take a pregnancy test.

Why does the morning-after pill affect your period?

The morning-after pill, like Julie, is made up of a synthetic hormone called levonorgestrel, which stops or delays the timing of ovulation (when the ovary releases an egg). Anytime you take a hormone, it will impact your hormone levels, which can often impact your period.

Our menstrual cycles are made up of four phases: menstrual, follicular, ovulatory, and luteal. Since the morning-after pill affects ovulation, a chain reaction can occur where the other stages of your cycle become impacted or temporarily delayed, which is why some people experience an early or a late period.

Reminder that levonorgestrel is NOT an abortion-inducing drug. Like daily contraception, for example, it stops you from getting pregnant and does not interfere in any way with an already fertilized egg—aka, an already established pregnancy.

Morning-after-pill side effects compared to typical period symptoms

Not everyone who takes the morning-after pill will experience side effects, but those who do can expect them to be pretty similar to period symptoms. The majority of symptoms from levonorgestrel, the main ingredient in Julie, are usually felt within 24 hours of taking it.

Common side effects include:

  • Changes in your period
  • Nausea
  • Lower Stomach pain
  • Tiredness
  • Headache
  • Dizziness
  • Breast tenderness

These symptoms tend to subside within a day or two. Levonorgestrel is FDA-approved and proven to be safe when taken as directed.

How long does the morning-after pill affect your period?

Typically just for one menstrual cycle. Most people notice that their period starts either a few days early or a few days late, though some people have reported a two-week delay in menstruation. However, a late period does not always mean pregnancy; If it’s been 7 days after your expected period date, it’s best to take a pregnancy test.

Remember, changes to your current cycle may be expected when taking Julie, but everything should return to normal the next time you get your period.

When to take a pregnancy test

We know that a delayed or missed period can be super stressful, but remember that there are many reasons why your period could be late.

As a general rule of thumb, it’s best to take a pregnancy test if:

— You’ve taken the morning-after pill and 7 days have passed since you’d normally get your period

— It’s been 3 weeks since you took the morning-after pill and your period still hasn’t come

— 21 days have passed since the date of unprotected sex (pregnancy tests are usually the most accurate after 3 weeks)

— You had unprotected sex after taking the morning-after pill and didn’t use emergency contraception again (emergency contraception does not protect against future unprotected sex)

If you have other questions or concerns, or if you experience severe lower abdominal pain and/or persistent bleeding, contact your medical provider.

If you are pregnant, levonorgestrel, the main ingredient in Julie, will not impact or harm your pregnancy. You can take Julie knowing that no matter what happens, you will not harm your body or a potential pregnancy.

Questions about the morning-after pill, pregnancy prevention, and safe sex? Head to After Sex to ask our team of doctors any questions you have.

When used as directed, Julie is safe and effective. Common side effects may include changes in your period, nausea, lower stomach pain, tiredness, headache, dizziness and breast tenderness. Julie will not protect you from HIV and other sexually transmitted diseases.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any medication