Birth control pills contain synthetic hormones that are just like the hormones naturally produced in a woman’s body. The two most common types of pills are the minipill and the combination pill.

The minipill contains just one hormone, progestin. The combination pill contains two hormones, estrogen and progestin. Both types of birth control pills are 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 can’t 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.

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 and your doctor may need to reevaluate the medication you’re taking.

The most common side effects include headache, nausea, breakthrough bleeding, and breast tenderness.

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.

Bleeding during your active pill days instead of only during your placebo pill days is a common side effect of birth control pills in the first months on the pill. 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.

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

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. But this isn’t 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.

If you’re still experiencing side effects after three or four months 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.

When you and your doctor decide 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 fill the prescription.

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.

Overlapping

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.

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 any anxiety. Condoms provide protection from sexually transmitted diseases as well.

Buy now: Shop for condoms.

When to take your pills

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 medication and provide reminders.

Importance of placebo pills

If you switched to a birth control pill that provides placebo pills, make sure to take them after you have finished the pills. Even though they don’t contain any active hormones, taking them 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.

Missing or skipping a dose

If you accidentally miss a dose one day, take two the next day. 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.

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 and your doctor decide to change your birth control pill, make sure you talk about how you can make the switch while preventing pregnancy.

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 negative for STIs in the last year.

Healthline and our partners may receive a portion of revenues if you make a purchase using a link above.