Why Birth Control Pills Expire

If you use birth control pills, you likely don’t want to gamble with reduced effectiveness. Do birth control pills have an expiration date? And if they do, are they still reliable afterward? Read on to learn more.

How Birth Control Pills Prevent Pregnancy

Birth control pills are a hormonal method of contraception, available as combination pills or progestin-only pills (often called minipills). Combination pills include both estrogen and progestin, while minipills contain only progestin.

Combination pills prevent pregnancy through three mechanisms. First, the hormones suppress ovulation. Second, they thicken cervical mucus, making it harder for sperm to reach an egg if ovulation does occur. Third, they thin the uterine lining, reducing the chance of implantation.

Progestin in the minipill works similarly by inhibiting ovulation in many users and increasing cervical mucus viscosity to block sperm movement.

What an Expiration Date Indicates

An expiration date on any medication indicates until when the manufacturer can vouch for the product’s safety and potency. Using medicines past their expiration can be risky.

After a drug’s expiration, it may lose strength or its chemical structure may change. At that stage, manufacturers can’t ensure the medication won’t degrade. For birth control pills, this loss of potency could increase the chance of an unintended pregnancy.

The U.S. Food and Drug Administration mandates that manufacturers print an expiration date on medication packaging. This can appear on the label or stamped on the container. If only a month is shown without a year, the pills are considered to expire on the final day of that month. For instance, a pack marked “May” for the current year remains usable throughout that month, but not afterward.

You should dispose of expired birth control pills appropriately. Most medication leaflets include disposal guidance, or you can locate a drug take-back program  nearby. Note that many pharmacies won’t swap out expired packs for replacements.

If you opt to throw expired pills in the trash, the FDA recommends these steps:

1. Mix the pills with an unpleasant substance such as used coffee grounds, cat litter, or soil.
2. Place the mixture in a sealed container or plastic bag.
3. Dispose of the sealed container in the trash.

Consequences of Taking Expired Birth Control Pills

Using expired birth control pills can raise your risk of becoming pregnant. If you find out your pills are expired, use an alternative barrier method like condoms until you can start a fresh pack.

How to Prevent Ending Up with Expired Pills

It’s easy to let pill packs lapse without noticing. If you obtain more than a month’s supply at once, be sure to use the oldest pack first. Taking your pill at the same time every day also helps maintain its effectiveness.

When taken consistently at the same time each day, birth control pills can be up to 99 percent effective — this is known as “perfect use.” With missed doses or irregular timing, the pill is about 91 percent effective, referred to as “typical use.”

Combination pills commonly come in 21- or 28-day packs. Both formats include 21 active hormone pills; 28-day packs add seven “reminder” pills without hormones.

With 21-day packs, you take one active pill each day for three weeks, then have a pill-free week before beginning a new pack.

With 28-day packs, you take the seven inactive pills during the last week. Skipping these reminder pills may lead to forgetting to start the next pack on schedule, which can alter your hormone levels and reduce contraceptive effectiveness.

Progestin-only pills are sold in 28-day packs, where every pill contains progestin and must be taken daily around the same time. There are no placebo pills in these packs.

For further reading on interactions and safety, consider topics such as birth control and alcohol, which may be relevant when reviewing overall contraceptive effectiveness and lifestyle factors.

Choosing the Right Birth Control for You

If daily adherence or pill expiration worries you, you might explore other contraceptive choices. Reversible alternatives include diaphragms, intrauterine devices (IUDs), and transdermal patches. Permanent solutions include vasectomy for men and tubal ligation for women.

When comparing options, consider:

• whether the method uses hormones
• its effectiveness
• its cost
• accessibility
• how soon you want to conceive in the future

The Bottom Line

Like other medications, birth control pills carry expiration dates. Using pills past that date could increase the chance of an unintended pregnancy, so it’s best to avoid the risk. Always check the expiration before starting a pack, and consult your doctor or pharmacist if you have questions or concerns.