Taking birth control in the form of a pill can provide many benefits for your health: It's a safe and reliable contraceptive, and it can help period headaches and other hormonal symptoms.
However, one of the most common side effects of birth control is breakthrough bleeding. Here, we'll talk about what breakthrough bleeding is, potential causes, and when you should contact your healthcare provider.
Short answer: Breakthrough bleeding on the pill
In general, there are several medical causes for abnormal vaginal bleeding, but doctors say breakthrough bleeding while taking birth control rarely signals a problem. Breakthrough bleeding, aka any unpredicted bleeding between periods, is a common side effect of the pill, or hormonal contraception.
Most of the time it only lasts during the first 3 to 6 months of starting the combination birth control pill (the pill that combines both the hormones estrogen and progesterone.)
If breakthrough bleeding happens, it doesn't necessarily mean your birth control isn't working or that you should stop taking the pill. Most patients are advised to continue taking it as directed to prevent unplanned pregnancy. That said, you should always chat with your healthcare professional if you have concerns.
What is breakthrough bleeding on the pill?
Breakthrough bleeding is any spotting or unscheduled bleeding that occurs between periods on the pill. When you're on the pill, the type of period you have is actually a withdrawal period. This is very similar to a period, but it's typically a bit shorter and lighter because the hormones used in birth control can stop the build-up of the lining of the uterus and ovulation won't occur.
For those that are on other types of birth control, such as a hormone IUD or copper IUD, breakthrough bleeding is also a common instance for the first 3 to 6 months, but the specific causes and timelines may differ as they are different types of contraception. For breakthrough bleeding on the pill, it will depend on the type of hormonal birth control pill you take and other health factors.
Combined oral contraceptive
A combined oral contraceptive pill contains estrogen and progestin. If you take a combined oral contraceptive, you'll typically have a scheduled period every 28 days.
Many popular brands are low-dose ethinyl estradiol pills---hormonal contraception with two hormones---and low-dose, or lower estrogen. However, some brands like Seasonale can be used as extended-cycle birth control. The Mayo Clinic says that breakthrough bleeding is more likely with continuous and extended cycle schedules than with the traditional 28-day schedule.
Irregular bleeding is a pretty common side effect of the minipill, or progestin-only pill, which usually comes in a 28-day pack with a break of 4 days. So for those taking the mini-pill, breakthrough bleeding is any bleeding that happens during your 28-day pack.
Why you experience breakthrough bleeding on birth control
The exact reason why you are experiencing breakthrough bleeding can vary. However, know that breakthrough bleeding overall is a common occurrence for women on the pill.
If you are looking to get to the bottom of why this might be happening to you, there are some common reasons you may experience breakthrough bleeding. Importantly, this article provides general information about breakthrough bleeding and should not be considered medical advice. We encourage you to reach out to your medical provider to discuss your unique circumstances.
A new birth control prescription
If you just started the pill, and it's within the first 3 months of being on it, breakthrough bleeding is pretty common. In one study, 1 out of every 10 women experienced breakthrough bleeding in their first six menstrual cycles on the pill. If you continue to experience breakthrough bleeding after 3 to 4 months, you may want to consult your healthcare provider to see if another pill or contraception may be better.
Skipping your period while on the pill
With a combined oral contraceptive pill, you can decide to skip your period by using only the active pills in your pack. But as the Mayo Clinic says about continuous birth control regimens, one of the most common side effects of skipping your period is breakthrough bleeding. Researchers have found, however, that 90% of women that start extended continuous birth control regimens stop getting their period while taking their pill as directed.
Forgetting to take your pill
It's recommended to take the pill at the same time each day, but if you've [missed one or more pills or didn't take them at your usual time, you may experience breakthrough bleeding.
If you are unsure about what to do having missed a pill(s), you can ask your healthcare provider about what you should do.
Additionally, you should note that inconsistent use of the pill might decrease its effectiveness. So remembering to take your pill at the same time each day can help you prevent pregnancy and potentially avoid breakthrough bleeding.
You may experience breakthrough bleeding if you are on the pill and you smoke tobacco products. The Mayo Clinic says that smoking cigarettes while on the pill can significantly increase your chances of rare, serious side effects, as well as the more common ones like changes in menstrual bleeding patterns. This includes a greater chance of spotting between periods.
How long does breakthrough bleeding on the pill last?
Usually, breakthrough bleeding and other common side effects of oral contraceptives should resolve over time. The specific amount of time will vary for different women and spotting could come and go within the first 3 to 6 months of being on the pill if you are just starting.
Could you be pregnant?
Birth control pills have progestin, a hormone that primarily helps prevent ovulation (when an ovary releases an egg), thus preventing pregnancy. Progestin also makes it harder for sperm to get through by making cervical mucus "unfriendly."
As we've mentioned, breakthrough bleeding is very common when taking the pill, and does not necessarily mean the birth control isn't working or isn't a safe option for contraception.
In general, the CDC says the pill has a failure rate of 7% with typical use (includes incorrect or inconsistent use). With perfect use (following the directions for use), the pill is 99.97% effective.
However, if you've skipped, missed or adjusted the timing of taking your pill, it could impact its effectiveness, and you could have an increased chance of getting pregnant. If you have concerns, it might be a good idea to consult with your healthcare provider or take a pregnancy test.
Other causes for bleeding
If you have been bleeding for more than 7 days straight, it could be due to another health concern and may not be breakthrough bleeding. You may want to get medical advice as it could be another health condition causing the [bleeding such as:
Pelvic inflammatory disease
Sexually transmitted infections (such as gonorrhea or chlamydia)
If you are concerned about any of the above, contact your OBGYN or healthcare provider.
How to stop breakthrough bleeding
Unfortunately, there isn't one solution to breakthrough bleeding, but there are a few things that might help.
Take your birth control pills as directed
If you smoke tobacco products, quitting may improve breakthrough bleeding
If you've been skipping your period by only taking active pills in your pack, consider a scheduled break to allow a withdrawal period and then continue your new pack as directed
For the most part, breakthrough bleeding often resolves itself independently and may be different for every woman. If you are experiencing breakthrough bleeding, it's a common side effect, especially if you just started the pill. However, if you still have questions or concerns about breakthrough bleeding, talk with your OBGYN or healthcare provider to learn more.
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