Birth control pill FAQ: Benefits, risks and choices

Get the facts about common concerns and questions about birth control pills.By Mayo Clinic Staff

If you take the birth control pill (oral contraceptive), you're probably happy with its convenience and reliability. Still, you may have questions about how birth control pills could affect your health, the benefits and risks of birth control pills, and newer options available.

Can I use birth control pills to delay or stop my period?

Yes, you can. Birth control pills were once only packaged as 21 days of active hormone pills and seven days of placebo pills. While taking placebo pills, menstrual period-like bleeding occurs.

Today women have many more options — from regimens with 24 days of active pills and four days of placebo pills to regimens that are all active pills.

Some extended-cycle pill regimens have active hormone pills every day for three months, followed by a week of placebo (Seasonale) or low-dose estrogen pills (Seasonique, LoSeasonique). You experience menstrual bleeding during that week. Newer extended-cycle regimens involve taking active pills continuously for one year and can stop all menstrual bleeding.

Continuous or extended-cycle regimens have several potential benefits. They prevent hormone changes responsible for bleeding, cramping, headaches and other period-related discomforts. It can be convenient to skip a period during important events or trips. For women who experience iron deficiency due to heavy menstrual bleeding, using continuous regimens can reduce bleeding and there is less chance of developing iron deficiency.

Unscheduled bleeding and spotting often occur during the first few months on this type of regimen. It usually stops with time, but it continues in some women long after using the pills.

Do I need special pills or can I use ordinary birth control pills to prevent having a period?

There are birth control pill regimens designed to prevent bleeding for three months at a time or for as long as a year. But it's possible to prevent your period with continuous use of any birth control pill.

This means skipping the placebo pills and starting right away on a new pack. Continuous use of your birth control pills works best if you're taking a monophasic pill — with the same hormone dose in the three weeks of active pills.

If I plan to have a baby, how soon after stopping the birth control pill can I conceive?

Most women ovulate again about two weeks after stopping the pill. As soon as you ovulate again, you can get pregnant. If this happens during your first cycle off the pill, you may not have a period at all. Check a pregnancy test if you've had unprotected intercourse and your period hasn't returned.

Is there an advantage to waiting a few months after stopping the pill before trying to conceive?

Doctors were once concerned that if you conceived immediately after stopping the pill, you had a higher risk of miscarriage. However, these concerns have proved to be largely unfounded. The hormones in birth control pills don't remain in your system.

Most women start periods again a few weeks after they stop using the pill. However, if your periods were infrequent before you started taking the pill, they will likely be that way again after you stop the pill. Some women find that it takes a couple of months before they return to regular ovulation cycles. After stopping the pill, if you're not ready to conceive, then you may want to consider using a backup form of birth control.

What happens if I stop taking the birth control pill and my period doesn't come back?

If you don't have a period for several months, you may have what's known as post-pill amenorrhea. The pill prevents your body from making hormones involved in ovulation and menstruation. When you stop taking the pill, it can take some time for your body to return to normal production of these hormones.

Your period typically resumes within three months after you stop taking the pill. But some women, especially those who took the pill to regulate their menstrual cycles, may not have a period for several months.

If you don't have a period within three months, take a pregnancy test to make sure you're not pregnant and then see your doctor.

Will a pregnancy test be accurate if I'm taking the birth control pill?

You can get accurate results from a pregnancy test while you're on the pill. Pregnancy tests work by measuring a specific pregnancy-related hormone — human chorionic gonadotropin (HCG) — in your blood or urine. The active ingredients in birth control pills don't affect how a pregnancy test measures the level of HCG in your system.

What happens if I take birth control pills while pregnant?

Don't worry if you kept taking your birth control pill because you didn't know you were pregnant. Despite years of this accident happening, there's very little evidence that exposure to the hormones in birth control pills causes birth defects. Once you learn that you're pregnant, stop taking the birth control pill.

Can I use several birth control pills at once for emergency contraception?

It's possible to use standard estrogen-progestin birth control pills for emergency contraception, but check with your doctor for the proper dose and timing of the pills.

Certain types of pills are specifically designed to keep you from becoming pregnant if you've had unprotected vaginal intercourse. These medications are sometimes referred to as the "morning-after pill." Levonorgestrel pills (Take Action, Next Choice One Dose, and levonorgestrel .75) are available over-the-counter for women age 17 years and older. Younger women need a prescription for these medications.

Plan B One-Step — a single-dose regimen — is available over-the-counter for women of any age and should be used within 72 hours of unprotected intercourse. Plan B — a two-dose regimen — is available over-the-counter for women age 18 and older; those age 17 and younger need a prescription. These emergency contraceptives are available at drugstores, as well as health clinics and Planned Parenthood.

Ulipristal acetate (ella) is another type of pill approved for emergency contraception. It's a nonhormonal medication that prevents the effects of the body's natural hormone progesterone. It's available only by prescription. This medication is taken as a single dose for up to 5 days after unprotected intercourse.

May 04, 2016 See more In-depth