Oral Contraceptive Pills (OCP): What You Should Know

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Oral contraceptives (OCP) are birth control pills. They are sometimes referred to as hormonal contraceptives or simply the pill. Their primary purpose is to prevent pregnancy, but they can also help with acne, premenstrual syndrome (PMS), heavy menstrual bleeding (period), and cramping.

OCPs do not prevent sexually transmitted infections (STIs). 

This article reviews the types of OCPs, their effectiveness, benefits, side effects, costs, and where to get them. 

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Oral contraceptives use synthetic female hormones to prevent pregnancy. Combination pills and progestin-only (minipills) are the two main OCP types. Your healthcare provider may instruct you to take them conventionally, for extended use, or continuously. 

Combination Birth Control Pills

Combination birth control pills are the most commonly prescribed. They contain synthetic versions of the female hormones estrogen (ethinyl estradiol) and progesterone (progestin). 

Combination pills prevent pregnancy by stopping the ovaries from releasing an egg (ovulation) and causing changes to the lining of the uterus.

Common Combination Birth Control Examples

Some common combination birth control pills include:

  • Alesse (levonorgestrel and ethinyl estradiol)
  • Ortho Tri-Cyclen Lo (norgestimate, ethinyl estradiol)
  • Loestrin (norethindrone acetate and ethinyl estradiol)
  • Lo/Ovral (norgestrel and ethinyl estradiol) 
  • Yaz (drospirenone and ethinyl estradiol)

Progestin-Only Pills

Progestin-only pills are also called the minipill. This pill does not contain estrogen. It prevents pregnancy in a similar way as the combination pill, but it also thickens cervical mucus to make it more difficult for sperm to reach an egg if ovulation does occur.

Some common progestin-only OCPs include Camila, Errin, and Heather (norethindrone).

Conventional Pack

A conventional birth control pack has either 21 active and seven inactive pills or 24 active and four inactive pills. When taking a conventional pack, vaginal bleeding occurs once a month while taking the inactive pills.

Monophasic, Biphasic, and Triphasic

Combination birth control may contain the same dosage (strength) each day or have varying dosages taken in phases. These are categorized as:

  • Monophasic (same dose every day)
  • Biphasic (one dose for the first half and another for the second half)
  • Triphasic (one dose for the first five to seven days, another dose for the next five to nine days, and a third dose for the last five to 10 days)

Extended-Use Pills 

If your healthcare provider recommends you take the active pill and skip the inactive pill for longer than the usual 21 days, this is called extended use. When you take a break from the pill, you will usually experience withdrawal bleeding.

Seasonique (levonorgestrel/ethinyl estradiol) is an example of an OCP used for extended use. With it, you take active pills for 84 days (12 weeks) and inactive pills for one week before starting the next 12 weeks. 

Continuous-Use Pills 

Continuous-use pills is similar to extended-use pills. The difference is that you don’t take a break from hormones for a year or more. You do not typically have withdrawal bleeding when taking birth control this way. 

Typically, just the progestin-only pills are taken continuously. However, Amethyst (levonorgestrel and ethinyl estradiol) is an example of a combination pill that you can take continuously for one year. 

Sometimes it takes trying different brands or types of OCPs to find the one that works for you. Small changes in the hormone dose can cause side effects for you that another type, dose, or brand does not.


Oral birth control pills are 99% effective when taken as directed. This means consistently and correctly, every day at the same time.

With typical use (not always consistent or correct use) the failure, or pregnancy rate, for women using oral contraception is 4%–7%. 

Why Is It Important to Take Birth Control Every Day at the Same Time

Taking birth control every day at the same time is what suppresses ovulation and increases effectiveness. Using a birth control reminder app or setting the alarm on your phone can help ensure consistent use.

Missed Doses

If you’ve been taking birth control and miss a dose, take the missed pill as soon as you realize it, then continue taking it at your usual time daily. This may mean you take two pills on the same day. While missing one pill only slightly increases your risk of pregnancy, you may want to consider additional contraception for seven days. 

If you miss two or more pills, continue taking them at the usual time. In this case, healthcare providers recommend using backup contraception, such as condoms, for seven to nine days.

If you’ve never taken birth control pills before or are restarting them, use a backup method of birth control for at least the first seven to nine days. 

Emergency Contraception

Emergency contraception is available over the counter. It is also called the morning-after pill. It’s used as soon as you have unprotected sex or contraceptive failure. 


The primary purpose of OCPs is to prevent pregnancy. However, some also help with: 

  • Endometriosis (painful condition in which uterine tissue grows outside the uterus) 
  • Heavy menstruation (bleeding)
  • Heavy menstrual cramping
  • Irregular menstruation
  • Ovarian cysts
  • Premenstrual dysphoric disorder (PMDD)
  • Premenstrual syndrome (PMS)

Benefits of Combination Pills

In addition to the benefits mentioned above, healthcare providers often prescribe combination pills to prevent or treat acne. 

Benefits of Progestin-Only Pills

The benefits of taking progestin-only pills include:

  • You can take them immediately after childbirth or while breastfeeding.
  • They do not increase the risk of high blood pressure or cardiovascular (heart) disease.
  • You can take them with a history of high blood pressure or blood clots.
  • They are safer for women who are over 35 or smoke.
  • They may have fewer side effects such as nausea and headache.

Benefits of Extended or Continuous-Use Pills

Healthcare providers may recommend extended or continuous-use for people who want or need fewer or no periods. Reasons that this may be necessary include:

Other extended or continuous use benefits include improved ovulation suppression and better medication adherence. 

Side Effects

The most common side effects are breakthrough bleeding or spotting, especially when first starting treatment. This is more common with progestin-only pills, but it can occur with combination pills. 

Other possible side effects of OCPs include:

  • Acne
  • Breast tenderness or enlargement
  • Brown or black skin patches
  • Change in appetite
  • Gum tissue swelling
  • Irritation or itching of the vagina
  • Menstrual bleeding (period) changes
  • Stomach upset
  • Weight loss or gain
  • White vaginal discharge
  • Unusual hair growth

While serious side effects from OCPs are uncommon, they often require medical attention. Talk to your healthcare provider if you experience any of the following:

  • Complete loss of appetite
  • Coughing up blood
  • Dark urine
  • Fatigue
  • Fever
  • Heavy menstrual bleeding
  • Leg pain
  • Light-colored stool (poop)
  • Rash
  • Severe headache
  • Severe vomiting
  • Shortness of breath
  • Swelling of legs, arms, hands, or ankles
  • Vision or eye problems

Rare But Severe Side Effects

There are rare but severe side effects of OCPs that require immediate medical attention. Call 911 if you have any of the following:

  • Arm or leg weakness or numbness
  • Chest pain or heaviness
  • Fainting
  • Shortness of breath
  • Speech problems


Pill packs can range from $0 to $50 per pack, depending on the brand and your insurance coverage. Typically, generic options are less expensive than brand-name OCPs and often cost less than $10 per month. Most insurance plans offer birth control pills for free.

If you don’t have insurance, government programs also help with costs for those who qualify. You can ask your healthcare provider if the manufacturer of your brand of birth control offers a discount card or look into prescription discount plans

OCPs require a prescription. However, you can request a virtual telehealth visit through websites such as Planned Parenthood. Twenty U.S. states allow pharmacists to prescribe birth control.


Oral contraceptives (OCP) are birth control pills known as hormonal contraceptives or the pill. Their primary purpose is to prevent pregnancy, but they can also help with acne and period problems. OCPs do not prevent sexually transmitted infections (STIs).

The cost for birth control usually ranges from $0 to $50. However, most insurance companies provide it for free. Government programs, discount cards, and prescription discount plans may help if finances are a barrier.

A Word From Verywell

With so many birth control options, the choice can feel overwhelming. Learning about each type helps you make an informed decision. Working with a healthcare provider can also help you choose which type best suits you. 

Frequently Asked Questions

  • What is OCP birth control?

    Oral contraceptive pills (OCP) are birth control pills primarily used to prevent pregnancy. They can also help treat acne or period-related problems. They do not protect against sexually transmitted infections (STIs).

  • How reliable is OCP birth control?

    When OCP birth control is taken perfectly—every day at the same time—it is 99% effective. With typical use (not always consistent or correct use), it is 93-96% effective. 

  • Where do I get OCP birth control?

    You can request a prescription for birth control from your primary healthcare provider, gynecologist, or community health center. You can also sign up for a telehealth visit on the Planned Parenthood app and website. Once they write you a prescription, you can pick it up at a pharmacy or have pills mailed to you. In 20 of the U.S. states, pharmacists can prescribe OCPs.

15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. Centers for Disease Control and Prevention. Progestin-only pills.

  4. National Library of Medicine (NIH). Progestin-only (norethindrone) oral contraceptives.

  5. UpToDate. Combined estrogen-progestin oral contraceptives: Patient selection, counseling, and use.

  6. Britton L, Alspaugh A, Greene M, McLemore M. CE: An evidence-based update on contraception. Am J Nurs. 2020;120(2):22-33. doi:10.1097/01.NAJ.0000654304.29632.a7

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  8. Teal S, Edelman A. Contraception selection, effectiveness, and adverse effects: A review. JAMA. 2021;326(24):2507-2518. doi: 10.1001/jama.2021.21392

  9. The American College of Obstetricians and Gynecologists. Combined hormonal birth control: Pill, patch, and ring.

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  12. Planned Parenthood. How do I get birth control pills?

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By Brandi Jones, MSN-ED RN-BC
Brandi is a nurse and the owner of Brandi Jones LLC. She specializes in health and wellness writing including blogs, articles, and education.