Birth control pills contain synthetic hormones just like ones naturally produced in a woman’s body. Two types of pills are most commonly used. The first type of pill, often called a minipill, contains just one hormone, progestin. The other option is the combination pill. This pill contains the two hormones estrogen and progestin. Both types of birth control pills are very effective and safe.

Birth control pills work in three ways. First, the hormones prevent your ovaries from releasing a mature egg during ovulation. Without an egg, sperm cannot complete fertilization. The mucus production on the outside of your cervix is also increased, which can prevent sperm from entering your uterus. The uterine lining is also thinned, which can prevent a fertilized egg from attaching.

What Are the Side Effects?

Many women taking birth control pills experience a few side effects in the first weeks and months after they start it. If your side effects don’t resolve after three or four months on the pill, contact your doctor. You may need to reevaluate the medicine you’re taking.

The most common side effects include:


Changes in hormone levels are a common cause of headaches. You may experience occasional headaches while your body becomes accustomed to the new level of hormones.


For some women, the dose of hormones may be too much, especially on an empty stomach. Taking your pill after a meal or before bed may help reduce nausea and upset stomach.

Breakthrough Bleeding

Bleeding during your active pill days instead of only during your placebo pill days is a common side effect of birth control pills. Many women experience unscheduled bleeding while on birth control. If this issue doesn’t resolve itself in three to four months, talk with your doctor about changing your pill.

Breast Tenderness

Increased hormones can make your breasts more tender and sensitive. Once your body is accustomed to your pill’s hormones, the tenderness should resolve.

What Causes These Side Effects?

Birth control pills increase your level of certain hormones. For some women, their bodies can absorb this change in hormones without any unwanted side effects. However, this is not the case for every woman.

Side effects of birth control are rarely severe. In most cases, the side effects will resolve once the body has a few cycles to adjust to the higher levels of hormones. This usually takes about three to four months.

Which Birth Control Is Right for You?

If you’re still experiencing side effects or if your side effects become more severe, make an appointment with your doctor. Most women can find a birth control pill that doesn’t cause problems and is easy for them to take. Don’t give up if the first pill you try doesn’t work well for you.

What to Consider When Switching

If you or your doctor decides it’s time to switch pills, there are a few things you should keep in mind. Make sure you discuss each of these topics with your doctor before you begin your new medicine.

How to Transition

When switching between pills, most doctors recommend that you go straight from one pill type to another with no gap or placebo pills in between. This way your level of hormones doesn’t have a chance to drop and ovulation can’t occur.

The Backup Plan

If you go straight from one pill to another without a gap, you may not need to use a backup plan or other form of protection. However, to be safe, your doctor may recommend you use a barrier method or other form of protection for up to seven days. Some providers recommend that you wait an entire month before having unprotected sex. Ask your doctor what’s best for you.


If you’re switching from another form of birth control to the pill, you should talk with your doctor about overlapping your two forms of birth control. It’s not necessary for every woman. To keep yourself protected, you should discuss how to end your original form of birth control and start the new one.

How to Switch Properly

For many women, the saying “It’s better to be safe than sorry” applies when switching between types of birth control pills. If it makes you feel more comfortable, use a backup protection method, such as condoms, until you’ve had a full cycle while on your new form of birth control. Knowing you have this extra protection may help alleviate unnecessary anxiety.

It’s important that you continue to take your pill every day at the same time. Missing a dose by several hours increases the likelihood you’ll begin ovulation. This increases your risk for an unplanned pregnancy. Many smartphones come equipped with a calendar that can remind you. Some smartphone apps are also designed to help you remember to take medicine and provide on-time reminders.

If you switched to a birth control pill that provides placebo pills, take these, too. Even though they don’t contain any active hormones, taking these will help you stay in the habit of taking a pill every day. This can also reduce the odds that you forget to start your next pack on time.

If you accidentally miss or skip a dose, call your doctor. Most doctors will recommend you take the missed dose as quickly as possible and then return to your regularly scheduled time. However, depending on the number of doses you skipped, your doctor may have another suggestion. This may include emergency contraception or barrier methods of contraception.

Birth control pills can help you prevent an unplanned pregnancy, but they don’t prevent sexually transmitted infections (STIs), including HIV. You should still consider a barrier method if you aren’t in a monogamous relationship or if you and your partner haven’t tested clean in the last year.


Switching between birth control pills is relatively easy and low risk. Developing a plan with your doctor can help make this transition as smooth as possible. Once you decide to change your birth control pill type, make sure you talk to your doctor about how you can make the switch while preventing conception.