This article was last updated on June 7, 2022.
In 1960, something happened that would change the course of women's health forever: the birth of the birth control pill (sorry, we had to). While the pill, also called the oral contraceptive, went through many iterations before it was deemed safe enough for public consumption, it was (and is!) an enormous victory for women who want ownership over the decision to have children, when to have them, and how many to have. The pill remains one of the most popular birth control methods in the United States.
In this piece, we'll give you all the information you need to consider whether or not the pill is the right form of birth control for you. Read on to get the answers to these questions:
- What is the pill and how does it work?
- What are the different types of birth control pills?
- What are the pros and cons of taking the pill?
- Does the pill impact fertility?
- Who shouldn’t take the pill?
- How much does it cost (and does insurance cover it)?
- How do you take the pill and what do you do if you miss a dose?
- Can the pill be used as emergency contraception?
What is the birth control pill?
Birth control pills are oral contraceptives using either a combination of hormones (progestin + estradiol) or just one (progestin) to prevent pregnancy.
Birth control pills come in a pack and you take one pill every day. Each type of pill has different amounts of placebo (inactive) pills that don’t contain hormones. The placebo pills in the pack are there to prompt your body to have something that resembles your period (more on this in a minute). If you don’t take these pills, you can skip bleeding altogether — and it doesn’t put you at an increased risk for pregnancy (but it might require you to get more refills than your insurance covers).
What are the main types of birth control pills?
Combination birth control pills: progestin + estradiol
When considering combination pills, there are a few categories of options to choose from:
The mixture of active and inactive pills (influencing how often you bleed):
- Conventional combo pill packs have 21 active pills (active = contains hormones) and seven inactive (placebo) pills, or 24 active pills and four inactive pills. You bleed when you take the inactive pills, but this bleeding isn't your period — it's actually withdrawal bleeding. "A withdrawal bleed refers to bleeding in the setting of hormone use, particularly when hormones are stopped," says Dr. Eva Luo, an OB-GYN at Beth Israel Deaconess Medical Center in Boston. “Ovulation does not occur when taking birth control pills, but this bleeding simulates the timing of menstrual bleeding.”
- Continuous dosing (or extended cycle) packs contain 84 active pills and seven inactive pills, so you only bleed four times a year.
The dose of estrogen and the type of progestin:
- The basic components of combined birth control pills are estrogen and progestin. The reason why you see several different brands of pills is they vary in the amount of estrogen and the type of progestin. This gives you and your provider the flexibility to find the combination that works best for your body. For example, low-dose birth control pills have the least amount of estradiol (0.02mg or 20mcg) and can be a good choice for people who have experienced unpleasant side effects (i.e., mood changes and nausea) from higher doses.
The amount of hormones in each pill:
- Monophasic pill packs: The active pills all contain the same amounts of estrogen and progestin, so you’re getting an equal dose throughout each pill cycle.
- Multiphasic pill packs: The amounts of hormones in active pills vary. The most popular kind of multiphasic pills are triphasic — they contain three different levels of estradiol in the pack. Triphasic pills most closely mirror the hormone fluctuations of your actual menstrual cycle. These pills cannot be used for continuous or extended use.
Combination pills protect against pregnancy right away if you start taking them within five days of the onset of your period. If you start them at another time, you'll need to take them for seven days and use backup birth control if you're having sex with a partner who has a penis.
Non-combination birth control pills (aka the minipill): progestin only
Non-combination birth control pills, or the minipill, come in a pack without any placebo pills. The most important thing to remember with the minipill is that the progestin only provides a short duration of contraceptive coverage: “We strongly encourage patients to take the pill at the same time every day to achieve maximum and reliable contraceptive benefit,” Dr. Luo says.
You can start taking the minipill any day of the month and you'll be protected from pregnancy after 48 hours, but most providers will still recommend using backup contraception for seven days.
How does the pill work? The science behind the oral contraceptive
You might have heard that the pill “tricks” your body into thinking you're pregnant, but that’s not entirely accurate.
Progestin and estradiol, the synthetic versions of progesterone and estrogen that combination birth control pills (more on those in a second) contain, work by:
- Changing the hormonal feedback loops and suppressing your levels of gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) — this effectively shuts down your menstrual cycle and prevents the development and release of eggs
- Thickening your cervical mucus to prevent sperm from getting to an egg
- Thinning the endometrium (or the lining of the uterus) to make implantation of an embryo more difficult
- Slowing down the egg’s journey through the fallopian tubes
On the other hand, non-combination birth control pills (aka minipills), which only contain progestin, work differently depending on the form of progestin. Minipills with norethindrone thicken cervical mucus, thin the endometrium, and slow down the egg’s journey through the fallopian tubes — but don't suppress ovulation for all users. Minipills with drospirenone (a newer option) do suppress ovulation.
The upsides, the downsides, and the good-to-knows
Now, the birth control pill is incredibly popular — so you might already be pretty familiar with the pros and cons. When you speak with your doctor about your options, they’ll give you all the details. But if you feel like prepping before the check-in, keep reading for the benefits, risks, and plenty of other useful info to help you make the right decision for you.
How effective are birth control pills?
According to the Guttmacher Institute, the pill, along with female sterilization, has been the most popular means of birth control in the US since 1982. It's pretty clear why: The pill is really, really good at pregnancy prevention. When used perfectly, it's 99% effective — but since perfect use doesn't actually exist, it's more like 91% effective.
In addition to preventing pregnancy, there are quite a few benefits to taking the pill. Let's take a look.
The benefits of the combination pill:
- Lowers the risk of colorectal, endometrial, and ovarian cancers
- Premenstrual syndrome relief
- Less severe menstrual cramps
- Improvement in acne
- Shorter, lighter, and more predictable periods, or fewer or no periods
- Reduction in heavy bleeding (and the anemia that comes with it)
- Reduced symptoms of endometriosis
- Improvement of unwanted hair growth as a result of polycystic ovary syndrome (PCOS)
The benefits of the minipill:
- Lowers the risk of endometrial cancer
- Can be taken if you have a history of these health conditions and cannot take birth control that contains estrogen. like blood clots, migraines, high blood pressure, or a high risk of heart disease)
- Less likely to interfere with breastfeeding (chestfeeding) than combo pills
What are the side effects of birth control pills?
The pill, like any type of birth control, does have some side effects. While some of them have been proven to be directly caused by the pill, others seem to be associated with the pill, but it isn’t clear if they’re caused by it.
Some side effects of the combo pill that are strongly backed by research:
- Irregular bleeding (more likely if you're taking the continuous dose or extended cycle pills)
- Breast/chest tenderness
- Increased risk of high cholesterol, heart attack, and stroke
- Increased risk of blood clots (especially for certain people, like if you smoke and/or are over 35 years of age)
Other side effects, like weight gain or depression, have been noted by people who’ve used combined oral contraceptives, but not shown in studies to be directly caused by them. This doesn’t necessarily mean that oral contraceptives don’t cause these side effects for individual users – but it does mean that when we look at large populations, we don’t see any causal link.
Dr. Luo adds: “You may see oral contraceptive pills being associated with an increased risk of cervical cancer and breast cancer, gallbladder disease, and liver disease. You and your doctor will decide based on your personal and family medical history if the birth control pill is the best contraceptive choice for you.”
You should reach out to your doctor immediately if you experience any of the following while taking the combination pill:
- Two missed periods or signs of pregnancy
- Difficulty speaking
- Eye problems, such as blurred or double vision or loss of vision
- Severe leg pain or swelling
- Chest pain
- New or worsening headaches
- Severe allergic skin rash
- Abdominal pain
- Jaundice (yellowish discoloration of the skin)
- Severe mood swings
- Breast/chest lumps
Some side effects of the minipill that people have noted:
- Irregular menstrual bleeding
- Ovarian cysts
- Decreased sex drive
- Breast/chest tenderness
- Weight gain
How can the pill impact fertility?
According to a 2013 study by researchers at Boston University, there's no evidence that oral contraceptives have a lasting effect on fertility or reproductive health. Researchers have found similar findings in more recent population-based studies and in meta-analyses as well (meaning we can be confident that oral contraceptives don’t have a lasting impact on fertility and reproductive health).
In another study of 60,000 oral contraceptive users, 20% of the participants became pregnant in their first cycle after stopping the pill, and 80% got pregnant in a year (regardless of what kind of pill they were taking).
If you decide you're ready to try to get pregnant, stop taking the pill — just know that it can take a few months for you to get back to your pre-pill cycles. (And no, you don’t need to do a birth control cleanse.)
Here’s what can impact your fertility:
- Untreated sexually transmitted infections, or STIs (since the pill doesn't protect against them)
- Certain conditions, like PCOS (the symptoms of which can be disguised while you're on the pill)
How much does the pill cost (and will insurance cover it)?
If you don't have insurance, the pill may cost you up to $50 per pack, and each pack lasts for one month. Planned Parenthood offers programs to make the ring (and other birth control options) affordable. With insurance, however, the pill may be low cost or even free. Check with your insurance provider to find out what they cover. You need a prescription for the pill, so remember to factor in the cost of a visit to the gynecologist, where you'll talk to your healthcare provider about what kind of pill would work best for you and when you'll start taking it.
Is there anyone who shouldn’t take the pill?
Your healthcare provider may recommend that you not take the combination pill if you:
- Smoke and are older than 35 years old
- Have high blood pressure that's hard to control
- Have a history of or current deep vein thrombosis or pulmonary embolism
- Have a history of stroke or heart disease
- Have a history of breast cancer
- Have migraines with aura
- Have diabetes-related complications, such as nephropathy, retinopathy, or neuropathy
- Have liver disease
- Have unexplained uterine bleeding
Your healthcare provider may recommend that you not take the minipill if you:
- Have a history of breast cancer
- Have a history of liver disease
- Have unexplained uterine bleeding
- Will have trouble remembering to take the pill at the same time every day
And if you’re taking any of these medicines or supplements, that may impact how well the pill works:
- Rifampin (an antibiotic)
- Griseofulvin (an antifungal)
- Certain HIV medicines
- Certain anti-seizure medicines
- St. John’s Wort
What’s it like to use the pill as birth control?
It's vital that you take the pill every day (and in the case of the minipill, at the same time every day), so do whatever you need to do to make that happen. If you’re looking for a few ideas, here are some pro tips from Planned Parenthood:
- Download a birth control reminder app (like this one)
- Set an alarm on your phone
- Keep your pill pack next to something you use every day, like your keys or phone
- Ask your partner to remind you
- Ask someone who also takes medicine every day to help you remember, and do the same for them
What do you do if you miss a birth control pill?
First, don’t panic! It happens. What you do next depends on which pill you use:
- A combination pill is considered "missed" if you don't take it 24 or more hours after you were supposed to.
- If you miss one active pill, take it as soon as you remember — even if that means taking two in one day. You don’t even need to use any backup birth control.
- If you miss two or more active pills, take the last pill you missed as soon as you remember — again, even if that means taking two pills on the same day. Throw away the other missed pills. Use emergency contraception if you have had unprotected sex in the last five days and don’t want to become pregnant, and use backup birth control until you’ve taken active pills for seven days in a row. (You can skip the placebo pills if you have fewer than seven active pills left in the pack.)
- If you miss placebo pills: Throw away the missed pills and take the next pill at the normal time.
- The minipill is considered "missed" if it's taken more than three hours late.
- If you miss a pill, take it as soon as possible — even if that means taking two at once. Consider using emergency contraception if you've had unprotected sex in the last five days and don't want to become pregnant.
Here’s how three women feel about taking birth control
Each individual will react differently to taking the pill, so we asked three women to share their experiences with oral contraceptives.
Sabine has been taking Marvelon, a combination birth control pill, for five years. "I do not think I would ever consider stopping it," she says. "It's excellent contraception, and my period is less painful."
"During my time on the pill, I was fine most of the time," says Katie, "but the mood swings when I got them were brutal and very tough on my significant other. In the end, I went off the pill and we went back to non-hormonal birth control. The sex was still fine and I didn't have to worry about hormone changes."
Rebecca has been on the pill since she was 16. "The pill really transformed my menstrual pain and cleared up my acne," she says. "The only hiccup was my senior year — I had a tear in my stomach lining that was making me very sick. I went off all my medication and then [ended up switching to Yaz (a combination birth control pill]. It's been the greatest gift. I know I have been extraordinarily lucky to have found a birth control that works for my body and economic situation so early in life."
Can the pill be used as emergency contraception?
Emergency contraception (EC) pills, also known as morning-after pills, are made from the same hormones as the pills we mentioned earlier. They prevent pregnancy when taken after unprotected sex the same way as the pill: by pausing ovulation and thinning the uterine lining.
So, can you take birth control pills if you need emergency contraception? The answer is... sometimes. Certain brands of birth control pills (such as Seasonale) can be safely used in increased amounts as EC. The Emergency Contraception Website has a full list of the pills that can be taken as EC, as well as information about dedicated EC pills like levonorgestrel (or Plan B One-Step).
If this info on birth control pills makes you think they might be the right option for you, talk about it with your doctor — and be sure to give them a full rundown of your medical history. And if you’re considering other contraceptive methods, we’ve got plenty more info and science waiting for you right here.
Since we’ve been talking a lot about hormones in this post, if you’re curious about checking in with yours (on or off the pill), do it from home with the Modern Fertility test.
This article was medically reviewed by Dr. Eva Marie Luo, an OB-GYN at Beth Israel Deaconess Medical Center and a Health Policy and Management Fellow at Harvard Medical Faculty Physicians, the physicians organization affiliated with the Beth Israel-Lahey Health System.