Top things to know
Birth control pills work, in part, by preventing ovulation and making cervical fluid hard for sperm to penetrate.
Missing pills might increase the chance of ovulation and make cervical fluid easier for sperm to travel through.
If you find it hard to take pills on time and don’t want to get pregnant, consider setting a daily reminder using Clue or trying a different kind of birth control.
If you've missed a pill or two, you are not alone! One study found that almost one in four people taking the pill missed at least one pill during their last cycle (1). Below, we cover what you should do when you miss a pill and the consequences of missing pills.
What should I do if I miss a pill?
What to do when you miss a pill depends on 1) What kind of pill you take (the combined pill with estrogen and progestin, or the progestin-only pill) and 2) How many pills you miss. The information leaflet that comes with your contraceptive pills should include specific instructions about what to do if you miss that specific brand of pill.
In general, the US Centers for Disease Control recommend the following (2):
Combined oral contraceptive pills (COCs) contain an estrogen and progestin. Often “active” pills that contain hormones are taken for 21 days followed by a 7-day hormone-free break during which you do not take pills or you take hormone-free placebo pills. Some combination pills are taken with shorter breaks (e.g. 4 days), fewer breaks (e.g. every 3 months), or no hormone-free breaks at all.
A combination pill is “missed” if you do not take it for 24 or more hours after you were supposed to.
In other words, you’ve only technically missed a pill, if it’s been more than 48 hours since your last active pill.
For example, if you took your pill at 9:00AM on Monday, you should take your next pill around 9:00AM on Tuesday. If you don’t remember to take your Tuesday pill until 11AM on Wednesday, you have missed the Tuesday pill, since it has been more than 48 hours since Monday’s pill. (This is different from taking a pill late - e.g., taking your Tuesday pill at 9:00PM instead of at 9:00AM.)
If you missed 1 active pill: Take the pill as soon as you remember, even if you have to take two pills on the same day. You do not need to use back-up birth control (e.g. condoms).
In our example above, this would mean you would take 2 pills on Wednesday.
If you missed 2 or more active pills: Take the last pill you missed as soon as you remember, even if you have to take two pills on the same day. Throw away the other missed pills. Consider using emergency contraception if you have had unprotected sex in the last five days and do not want to become pregnant. To protect against pregnancy, use back-up birth control (e.g., condoms) until you have taken hormonal pills for 7 days in a row. If there are less than 7 hormonal pills left in the pack after you take the last pill you missed, you can skip the hormone-free break by starting the next pack immediately.
From our previous example, this would mean you missed both your Tuesday pill and Wednesday pill and it’s now Thursday (in other words, it has been 72 or more hours since your last active pill). You should take the Wednesday pill and the Thursday pill, and throw away the Tuesday pill.
If you miss placebo pills: Throw away the missed pills and take the next pill at the normal time.
Progestin-only pills contain a progestin but do not contain estrogen. They are taken continuously, without any hormone-free breaks.
If you missed progestin-only pills: If you take a progestin-only pill more than 3 hours late (or more than 12 hours late if it contains 75 µg of the progestin desogestrel (3)), take one pill as soon as possible even if you have to take two pills on the same day. Continue taking one pill a day and consider using emergency contraception if you have had unprotected sex in the last five days and do not want to become pregnant. To protect against pregnancy, use back-up contraception (e.g., condoms) until you take the pill on time for two days in a row.
For example, if you were supposed to take your pill at 9:00AM on Monday, but didn’t take it until Monday 12:30PM, take your pill correctly on Tuesday and Wednesday and use back-up protection until Thursday.
Can I keep having unprotected sex?
To get pregnant, you need to ovulate normally, and sperm needs to be able to reach the fallopian tubes to fertilize the egg. When you take contraceptive pills, the hormonal changes that happen during the menstrual cycle are disrupted, ovulation is often prevented, and your cervical fluid is thickened. The science is fuzzy, but missing pills may make ovulation more likely and may make cervical fluid easier for sperm to penetrate on the way to the egg (4-9).
In short, people who miss one or more pills per cycle are more likely to have an unintended pregnancy than those who do not miss pills (10).
Missed pills are considered the main reason why the rate of unintended pregnancy in the first year of “typical” contraceptive pill use is about 7 out of 100 people (among “perfect users” 0.3 out of 100 people have an unintended pregnancy).
So, if you don’t want to risk getting pregnant, use back-up contraception or abstain from vaginal sex until your pill fully protects you – 7 days of active combination pills in a row or 2 days of progestin only pills in a row.
What if I take contraceptive pills to manage heavy bleeding or pain symptoms?
Combined and progestin-only pills are also used for the management of heavy menstrual bleeding, endometriosis-associated pain, and other cycle-related conditions and symptoms. Research shows that these symptoms can worsen during the hormone-free period (11) and it is possible that missing pills will also make these symptoms worse.
What if I miss pills regularly?
If you find yourself missing pills regularly, research shows that incorporating it into a routine or setting a reminder may help (12,13). You can also talk to your health care provider about switching to another kind of birth control—the patch is changed weekly, the vaginal ring stays in for three weeks, the shot lasts for three months, IUDs or the implant are effective for years, and sterilization (e.g., getting the fallopian tubes blocked or cut) is permanent. Non-hormonal and non-invasive forms of birth control, like male (external) or female (internal) condoms, diaphragms, or fertility awareness based methods are options too. Regardless of the type of birth control you try, using it consistently and correctly is important, so check in with your healthcare provider if you have any questions.