Combination birth control pills

Birth control pills: What are they?

The combination birth control pill, commonly known as the Pill, is an oral contraceptive that contains synthetic forms of two hormones, estrogen and progesterone. (Synthetic progesterone is known as progestin.)

With most brands, you take one pill every day for 21 days and then take nothing or a dummy pill that contains no hormones for the next seven. During this last week, your hormone levels drop off, causing you to get your period. When you've completed the 28-day cycle, you start a new pack of pills the very next day.

(Note: There's also a progestin-only birth control pill, known as the mini-pill. With typical use, it can be slightly less effective than the combination pill, but may be a good alternative for women who want to use an oral contraceptive but who are breastfeeding or can't take estrogen for some other reason.)

Are there different types of combination birth control pills?

There are dozens of brands (and many more generic versions) of combination pills on the market and they vary in cost, dosages, and types of estrogens and progestins.

Your prescription will come in a pack of 28 pills (or more, if you get more than one cycle's worth). In some cases, 21 of these are "active" pills and the other seven are hormone-free. In other packages, 24 pills are "active" and the other four are hormone-free.

In some brands, each active pill contains the same amount of hormones. In others, the amount of hormones varies depending on where you are in your cycle.

For women who would prefer to have their period less often, there is another option: extended-cycle combination pills. Some versions come in a pack of 91 pills – that is, 84 active pills followed by seven inactive pills. So, you take active pills for 12 weeks straight and then inactive pills for one week, during which time you'll get your period.

Birth control pills are quite small, but if you have trouble swallowing them, ask for a chewable Pill. If you use this chewable pill, be sure to drink a full glass of water immediately afterwards so the whole dose reaches your stomach.

How do birth control pills work?

When the Pill is taken as directed, the estrogen and progestin work together to prevent pregnancy primarily by suppressing ovulation. This means they keep your ovaries from releasing any eggs.

The progestin in the Pill has other contraceptive effects, too. It thickens your cervical mucus, making it hard for sperm to get through your cervix and into your fallopian tubes to fertilize an egg, if one is released. Finally, progestin thins the lining in your uterus, making it less likely that an egg would implant if it did get fertilized.

If you have a 28-pill pack, you take one active pill every day for 21 days and then a dummy pill – to keep you in the habit – for the next seven days and start the new pack immediately afterward. With a 21-pill package, you take one hormone pill each day for 21 days and then nothing for the next seven.

In both cases, if you start your pack on a Sunday, you take an active pill each day for 21 days, then dummy pills or no pills for the next seven days, and then begin the next pack on a Sunday, exactly four weeks from when you started the previous pack. As long as you've taken your pills exactly as directed – ideally, at the same time every day – you'll also be protected during the hormone-free week and don't need to use other contraception during that time. (You may need to use backup contraception for seven days after you first start the Pill – more on that in a second.)

It's important not to miss any active pills. Even if you're not having intercourse very often, you still need to take a pill daily – otherwise you won't be protected when you do have sex.

You'll usually get your period a few days after taking your last active pill.Women on birth control pills often have shorter, lighter periods. And some occasionally skip their period altogether for a cycle. If this happens to you, don't panic. It's highly unlikely that you're pregnant. You can take a home pregnancy test to be sure and continue taking your pills on schedule.

Some people also choose to skip their periods entirely by taking all the active pills in their monthly pack as directed, then omitting the placebo pills and moving onto the next pill pack.

How effective is the Pill?

When taken correctly and consistently (aka “perfect use”), the Pill is estimated to be about 99 percent effective in preventing pregnancy. This means that only one woman out of 100 who take the Pill properly will get pregnant in the first year.

If you don't take the Pill exactly as prescribed – for example, if you start a new pack late or miss pills without using back-up contraception – the likelihood that you'll get pregnant is much higher. And the more mistakes you make, the higher the risk. For the typical user, the Pill is about 91 percent effective, meaning nine women out of 100 will get pregnant in the first year.

So while the Pill is one of the most reliable methods of birth control available for women who never miss any pills, it's not the best method for everyone.

Although the Pill is an excellent contraceptive method, it doesn't offer any protection against sexually transmitted infections (STIs). So, if you're at risk for STIs, you'll need to use condoms as well.

How long does it take for birth control pills to work?

It depends on when you start taking them. If you start the Pill within the first five days of your period, you're immediately protected from pregnancy and don't need to use a backup method. If you start it at any other time in your cycle, you should use a backup method for the next seven days to protect yourself from pregnancy.

If you're less than six months postpartum, haven't had your period yet, and are exclusively breastfeeding, you will be protected from pregnancy right away and don't need an additional backup method after you start the Pill. If you're formula-feeding (or supplementing with formula) or are more than six months postpartum, you'll need to use another form of contraception for the next seven days after you start the Pill. (There are other caveats about taking the Pill after giving birth, which we'll elaborate on later.)

Side effects of birth control pills

Today's pills have a much lower risk of serious side effects than the first combination pills, which came on the market in the 1960s, because they contain much smaller amounts of hormones.

You may have spotting or bleeding between periods, known as breakthrough bleeding. The good news is that it usually goes away after a few cycles once your body adjusts to the change in hormone levels. It can also happen if you don't take your pills properly or skip the hormone-free week.

Some women feel a bit nauseated after taking their pills. If this is a problem for you, try taking them with meals or just before bedtime. Others report headaches, swollen or tender breasts, a bigger appetite, small changes in weight (gain or loss), bloating, a change in sex drive, or mood changes.

Most of these side effects go away within three months or so of starting the Pill. If breakthrough bleeding or other bothersome side effects don't stop after a few months, you can ask your practitioner about trying a different brand.

Some studies have shown that hormonal contraceptives, including the Pill, are associated with depression and suicide risk, especially in adolescents. There's still more research that needs to be done to know more conclusively how birth control pills can affect mental health, but it's worth noting.

Some women who wear contact lenses find they become uncomfortable when they start taking the Pill. If your eyes have become dry, try using saline eye drops or lubricants a few times a day. Consult your eye doctor if the problem doesn't go away.

Finally, some women develop melasma – areas of darkened skin, usually on the face – when they're taking combination pills. This is more likely to be an issue for you if you had skin darkening during pregnancy (aka chloasma).

You can lower your chances of getting melasma while you're on the Pill by protecting your skin from the sun with sunscreen and clothing. Melasma is not a health risk, but if you do develop it and find it bothersome, you'll want to switch to another method of contraception that doesn't contain estrogen.

It should also be noted that the Pill can slightly increase a person's risk of deep-vein thrombosis (DVT), stroke, and heart attack. In rare cases, a person can have more serious side effects from the Pill. Call your health practitioner immediately if you notice any of these symptoms:

• Sharp pain in the chest
• Back or jaw pain accompanied by nausea, sweating, or trouble breathing
• Shortness of breath
• Severe abdominal pain
• Soreness in one leg, or severe calf or thigh pain
• Migraine headaches, severe headaches of any kind, or headaches that are more intense than they were before you started the Pill
• Any neurological symptoms, including visual disturbances (such as blurred or double vision, temporary loss of vision, flashing lights or spots before your eyes), slurred speech, and tingling or weakness on one side of the body

You should also call without delay if you suddenly feel depressed or have severe mood swings. And, of course, contact your caregiver if you think you might be pregnant.

Pros and cons of taking birth control pills

As with any medication, there are pros and cons of the Pill that are essential for everyone to be aware of before deciding to use it for contraception.

There are lots of advantages to birth control pills. Along with being very effective at preventing pregnancy when used correctly, combined hormonal contraception like the Pill can also help make your periods lighter and less painful. Birth control pills can also help with hormonal acne and unwanted hair growth, and are often used to manage bleeding and pain from conditions like uterine fibroids and endometriosis.

From a practical standpoint, it's a relatively easy medication to start and stop. You just pick up the prescribed pills from your pharmacy and take them as directed. (No complicated or painful insertion procedure required, unlike some other types of birth control!) And because there are so many different types and doses of birth control pills, your doctor can just switch you to a different kind if you have side effects.

Additionally, if you want to stop the Pill to try and get pregnant, all you have to do is stop taking it. For many women, fertility returns as soon as they stop taking the Pill, but some may take a few months to get their periods back. (It might take longer to become fertile again on other birth control methods, such as the shot.)

 That said, there are some downsides in addition to the side effects outlined above. Because it can increase the risk of blood clots and other cardiovascular issues, people who smoke, have a history of blood clots or stroke, or who have migraines with aura should not take the Pill. Same goes for people who have had hormone-dependent cancers (like breast or uterine) in the past. People with serious liver disease or diabetes should also avoid taking birth control pills.

Certain medications might also affect how well birth control pills work, including the antibiotic Rifampin, some seizure meds like Trileptal, barbiturates, and the supplement St. John's Wort. If you have to take any of these regularly, then you should use a different form of contraception. Talk with your doctor whenever you're prescribed a new medication to ensure that it won't affect how well your birth control works.

Combined hormonal contraceptives like the Pill also can't be used until at least three weeks after giving birth, because those first few weeks postpartum come with a higher risk of DVT. If you're breastfeeding or have other risk factors for DVT, you'll have to wait even longer before you can start the Pill – a total of four to six weeks after giving birth. You'll have to use another form of contraception during that time period to prevent pregnancy.

Birth control pills are most effective when taken consistently every day, and get less effective if you skip a pill. If you think you'll have trouble taking the Pill properly, consider using another method, such as the IUD, implant, patch, ring, or the birth control shot (Depo-Provera), all of which are very effective.

What happens if I forget to take a birth control pill?

Your risk of becoming pregnant after missing combination pills depends on how many pills you've missed in a row, how many you've missed earlier in the pack, and where you are in your cycle. Check the instructions that come with your pills or any instructions that your caregiver may have given you for specific advice.

Here are some guidelines for protecting yourself:

• If you forget to start a new pack on time, just start taking your pills, one per day, as soon as you remember and use a backup method, like condoms, for the first seven days.
• If you are late in taking a pill or missed one pill, take it as soon as you remember. Then take the next one at your regular time. This means you may need to take two pills on the same day or even at the same time. (You may feel just a bit nauseated.) In this case, use a backup method for the next seven days.
• If you missed two pills or more, take the most recent pill ASAP. (Throw out the other missed pills.) Continue taking the rest of your pills as scheduled, and use a backup contraceptive method for seven days.
• If you missed a pill on the third week of your cycle (the week before the placebo pills), finish the hormonal pills as directed, then skip the placebo week and start a new pack of pills right away.
• If you started a pack late or missed one or more pills and had unprotected sex before you started retaking the pills or within seven days after restarting, using emergency contraception will reduce your risk of becoming pregnant.

If you experience vomiting within 24 hours after taking your pill, you should be fine. If you're vomiting repeatedly and can't keep your pill down or have diarrhea for more than 48 hours, follow the instructions above for missed pills.

If you continue to be ill, call your caregiver for specific instructions. In the meantime, keep taking your pills. And if you have sex while you're ill or during the seven days afterward, use a backup method. While you were sick, your body might not have absorbed enough hormones from the Pill to prevent pregnancy.

Finally, remember that you don't have to figure this out alone. If you feel at all confused about what to do about missed pills, don't hesitate to call your caregiver or the clinic that prescribed your pills, and in the meantime continue taking an active pill every day and use backup contraception as well. Also call your caregiver if you suspect that you're pregnant.

How much do birth control pills cost?

If you're an appropriate candidate for the Pill – that is, you have no health risks that make Pill taking unsafe (including smoking) and feel confident that you can follow the regimen of taking a daily pill – your health practitioner (or in some states, a pharmacist) can write you a prescription.

Thanks to the Affordable Care Act, insurance plans must cover at least one form of every type of FDA-approved prescription contraceptive method with no cost to you. Some plans are exempt from this mandate – such as religiously-affiliated employers – but there are often ways to still get coverage for your birth control.

If you're paying out of pocket, you can expect to spend up to $50 a month, depending on the brand and where you buy it. Planned Parenthood and Title X Family Planning Clinics are usually your best bet for good prices. You can find a Title X Family Planning Clinic on the Department of Health & Human Services website.