Bleeding after Plan B: Causes & side effects
Whether you got swept away in the heat of the moment or your primary birth control method went awry, you may be worried about an unplanned pregnancy. If so, Plan B can help. Plan B is a popular over-the-counter brand of emergency contraception.
Plan B, also known as the morning-after pill, works by preventing or delaying ovulation after unprotected sex. If you don’t ovulate, your partner’s sperm can’t fertilize your egg. Believe it or not, sperm can live in the reproductive tract for up to five days. Thus, Plan B must be taken within that time frame—the sooner you take Plan B, the more effective it is.
While Plan B may be able to prevent pregnancy, it can also cause some temporary side effects. One common side effect of Plan B is vaginal spotting or bleeding. Read on to learn more about Plan B bleeding and other side effects.
Why the morning-after pill can cause bleeding
Your body’s reproductive system is carefully regulated by two major sex hormones: estrogen and progesterone. Estrogen peaks during the first half of the menstrual cycle, while progesterone peaks during the second half. Once progesterone begins to drop, it can trigger your uterine lining to shed, resulting in the arrival of your period.
Plan B contains a synthetic version of progesterone, known as levonorgestrel. When your body receives this sudden influx of synthetic progesterone, it can respond by shedding the lining of your uterus.
So, can Plan B cause spotting? Yes, you may experience some spotting or bleeding after taking Plan B, regardless of where you’re at in your menstrual cycle. This spotting can set in as early as eight hours after taking your dose. Fortunately, spotting is often lighter and shorter than your regular period.
How does Plan B impact periods?
In addition to inducing spotting or bleeding, Plan B may also mess with your period’s regularity for a month or so.
After taking Plan B, you may notice that your period:
Arrives earlier or later than expected
Lasts for a longer or shorter amount of time than usual
Has a heavier or lighter flow than normal
Some people may experience heavy bleeding after Plan B, but this side effect is uncommon.
Note: Many people confuse Plan B with the abortion pill, which can cause heavy bleeding. However, Plan B is not an abortion pill. If you’re already pregnant when you take Plan B, your pregnancy will not be affected. There’s also no research to suggest that Plan B can negatively impact your developing fetus.
How common is bleeding from the morning-after pill?
According to a 2006 study on emergency contraception, bleeding after taking Plan B is a common side effect.
Here are a few statistics regarding the ways Plan B can impact your menstrual cycle and bleeding:
30% of people who take emergency contraception bleed within seven days of taking the medication.
31% of people report experiencing heavier periods after taking Plan B.
13% of people experience a delay in their period of seven days or more after taking emergency contraception.
Bleeding and menstrual cycle disruptions are two of the most frequently reported side effects of emergency contraception.
How to treat bleeding from the morning-after pill
If you bleed after taking Plan B, sorry—there’s not much you can do about it. Simply wait for it to pass and use your preferred period products in the meantime.
Spotting after Plan B vs. implantation bleeding
Unfortunately, Plan B pill is not 100% effective. It can be up to 89% effective, depending on how soon you take it after unprotected sex, where you are in your menstrual cycle, and your weight.
If Plan B doesn’t work, you may get pregnant. The very first stage of pregnancy is known as implantation. Implantation occurs when your fertilized egg attaches to your uterine lining. The implantation process may irritate your uterine lining and cause some spotting.
Since Plan B and implantation can both cause spotting, you may be wondering how you can tell the difference. The only surefire way is to take a pregnancy test. However, the following metrics may also help you differentiate between the two:
Plan B spotting – Spotting from Plan B typically sets in within hours to days of taking the medication. It usually only persists for a couple of days after that.
Implantation bleeding – Implantation bleeding typically begins 10 to 14 days after ovulation. If you know where you are in your cycle, you can estimate when this bleeding would take place if you were to become pregnant. Implantation bleeding can last anywhere from a few hours to a few days.
How common is pregnancy after taking Plan B?
Since it's recommended to take the emergency contraceptive pill right away, you may be wondering just how long does Plan B stay in your system and how effective is it? While the purpose of taking Plan B is to prevent pregnancy, no emergency contraception is 100% effective. It’s most effective when taken within 24 hours.
If you take Plan B within three days of having unprotected sex, it’s 75% to 89% effective. It’s estimated that seven out of eight people who would have gotten pregnant won’t if they take Plan B within three days.
As soon as you have unprotected sex, the clock on Plan B’s efficacy starts ticking. As a result, you’ll want to take it as soon as possible. You may even want to keep some Plan B on hand in case you ever need it in a pinch. Just make sure to store it properly and pay attention to its expiration date.
Note: If you throw up within two hours of taking Plan B, you may expel the medication. In this case, you should take another dose.
Other side effects of Plan B
Bleeding isn’t the only potential side effect you can experience after taking Plan B. Some other common side effects include:
Some of these side effects are similar to the early signs of pregnancy, which can be confusing for people who use Plan B.
The good news? Any side effects you experience from Plan B should subside within a few days. If they don’t go away, you may want to purchase a pregnancy test.
When to see a doctor
In most cases, you can take Plan B without consulting a doctor. That’s why it’s available over the counter.
However, you may need to check with your doctor before taking Plan B if you’re on barbiturates, St. John’s wort herbal supplements, antibiotics, antifungals, or prescription medications for seizures or HIV. These drugs may render Plan B ineffective.
You should also see your doctor after taking Plan B if you:
Haven’t gotten your period within four weeks
Have irregular menstrual bleeding for more than one to two months
Experience very heavy bleeding for multiple days or spotting for more than a week
Develop itchiness or a rash
Experience severe abdominal pain
Are worried that you may be pregnant
Alternatives to Plan B
Plan B isn’t the only emergency contraception you can choose from. Another option is ella, which requires a prescription.
But what’s the difference between Ella vs. Plan B? Like Plan B, ella can prevent pregnancy if taken within five days of unprotected sex. It’s around 85 percent effective when taken properly.
Unlike Plan B, ella’s efficacy doesn’t wane over the first five days. It’s also more effective for individuals who weigh 155 to 195 pounds than Plan B.
Plan A birth control options
Plan B and other emergency contraceptives can certainly come in handy when you’ve had unprotected sex. However, they’re not meant to take the place of primary birth control methods. So, can you take Plan B on birth control? The short answer is, yes. Plan B is an emergency contraceptive pill meant to be an additional measure alongside birth control pills and other methods.
Some preventative measures you can take to avoid pregnancy before having intercourse include using:
Fertility awareness methods
Each of these birth control methods comes with different benefits and drawbacks. Your healthcare provider can help you select the best option for you.
To sum it up, bleeding after taking Plan B is a common side effect. Whether you experience bleeding or not, the Plan B emergency pill can provide you with some peace of mind after impromptu intercourse with inadequate protection.
If you want to prevent pregnancy going forward, you can explore your birth control options with The Pill Club.
The Pill Club: Find the birth control that’s right for you
Here at The Pill Club, we provide prescription birth control, emergency contraception, and skin care online. We carry over 120 brands of birth control. When you sign up with us, all you have to do is answer a few questions during an online consultation. After that, our healthcare team can help you determine the right contraception method for your needs and lifestyle.
If our medical team determines a prescription is right for you, we’ll ship your birth control or emergency contraception to your home for free in discreet packaging. Thanks to our convenient auto-refill process, you can skip the monthly trek to the pharmacy and opt to simply await your refills from home. We’ll even throw in a few self-care extras just for fun. The best part? Your birth control can be affordable. It can cost as little as $0 with most insurance.
Are you ready to take control of your reproductive health? Sign up with The Pill Club today.
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