How does oral birth control work

The birth control pill also called "the Pill" is a daily pill that contains hormones to change the way the body works and prevent pregnancy.

Hormones are chemical substances that control the functioning of the body's organs. In this case, the hormones in the Pill control the ovaries and the uterus. Most birth control pills are "combination pills" containing a mix of the hormones estrogen and progesterone to prevent ovulation the release of an egg during the monthly cycle.

A woman cannot get pregnant if she doesn't ovulate because there is no egg to be fertilized. The Pill also works by thickening the mucus around the cervix, which makes it difficult for sperm to enter the uterus and reach any eggs that may have been released.

The hormones in the Pill can also sometimes affect the lining of the uterus, making it difficult for an egg to attach to the wall of the uterus. Most combination pills come in either a day pack or a day pack.

One hormone pill is taken each day at about the same time for 21 days. Depending on your pack, you will either stop taking birth control pills for 7 days as in the day pack or you will take a pill that contains no hormones for 7 days the day pack. A woman has her period when she stops taking the pills that contain hormones. Some women prefer the day pack because it helps them stay in the habit of taking a pill every day.

There is also a type of combination pill that decreases the frequency of a woman's period by supplying a hormone pill for 12 weeks and then inactive pills for 7 days.

This decreases the number of periods to one every 3 months instead of one every month. Another kind of pill that may change the number of monthly periods is the low-dose progesterone pill, sometimes called the mini-pill. This type of birth control pill differs from the other pills in that it only contains one type of hormone — progesterone — rather than a combination of estrogen and progesterone. It works by changing the cervical mucus and the lining of the uterus, and sometimes by affecting ovulation as well.

The mini-pill may be slightly less effective at preventing pregnancy than combination pills. Continue to take oral contraceptives every day even if you are spotting or bleeding, have an upset stomach, or do not think that you are likely to become pregnant. Do not stop taking oral contraceptives without talking to your doctor.

Oral contraceptives are also sometimes used to treat heavy or irregular menstruation and endometriosis a condition in which the type of tissue that lines the uterus [womb] grows in other areas of the body and causes pain, heavy or irregular menstruation [periods], and other symptoms.

Talk to your doctor about the risks of using this medication for your condition. This medication may be prescribed for other uses; ask your doctor or pharmacist for more information. If you miss doses of your oral contraceptive, you may not be protected from pregnancy. You may need to use a backup method of birth control for 7 to 9 days or until the end of the cycle.

Every brand of oral contraceptives comes with specific directions to follow if you miss one or more doses. Carefully read the directions in the manufacturer's information for the patient that came with your oral contraceptive. If you have any questions, call your doctor or pharmacist. Continue to take your tablets as scheduled and use a backup method of birth control until your questions are answered. Oral contraceptives may increase the chance that you will develop liver tumors.

These tumors are not a form of cancer, but they can break and cause serious bleeding inside the body. Oral contraceptives may also increase the chance that you will develop breast or liver cancer, or have a heart attack, a stroke, or a serious blood clot.

Talk to your doctor about the risks of using oral contraceptives. Some studies show that women who take oral contraceptives that contain drosperinone Beyaz, Gianvi, Loryna, Ocella, Safyral, Syeda, Yasmin, Yaz, and Zarah may be more likely to develop deep vein thrombosis a serious or life-threatening condition in which blood clots that form in the veins, usually in the legs and may move through the body to the lungs than women who take oral contraceptives that do not contain drosperinone.

However, other studies do not show this increased risk. Before you begin taking oral contraceptives, talk to your doctor about the risk that you will develop blood clots and about which oral contraceptive or other method of birth control may be the best choice for you.

Oral contraceptives may cause other side effects. Call your doctor if you have any unusual problems while taking this medication. Keep this medication in the packet it came in, tightly closed, and out of reach of children.

Store it at room temperature and away from excess heat and moisture not in the bathroom. Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. It is important to keep all medication out of sight and reach of children as many containers such as weekly pill minders and those for eye drops, creams, patches, and inhalers are not child-resistant and young children can open them easily.

To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. In case of overdose, call the poison control helpline at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at Keep all appointments with your doctor and the laboratory.

You should have a complete physical examination every year, including blood pressure measurements, breast and pelvic exams, and a Pap test.

Follow your doctor's directions for examining your breasts; report any lumps immediately. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. The Kaiser Family Foundation. Oral Contraceptive Pills. Published May 23, The Department of Health of Manila. Kaiser Family Foundation. San Francisco, California; May 23, Your Privacy Rights.

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We and our partners process data to: Actively scan device characteristics for identification. I Accept Show Purposes. Is There a Right Time to the Pill? Was this page helpful? Thanks for your feedback! Sign Up. What are your concerns? Each pill has the same amount of hormone in it. One pill is taken each day for 21 days and then no pills are taken for the next 7 days.

Microgynon, Marvelon and Yasmin are examples of this type of pill. Phasic pills contain 2 or 3 sections of different coloured pills in a pack. Each section contains a different amount of hormones. Phasic pills need to be taken in the right order. Logynon is an example of this type of pill. There are 21 active pills and 7 inactive dummy pills in a pack. The two types of pill look different. One pill is taken each day for 28 days with no break between packets of pills.

Every day pills need to be taken in the right order. Microgynon ED is an example of this type of pill. Follow the instructions that come with your packet. If you have any questions, ask a doctor, nurse or pharmacist. It's important to take the pills as instructed, because missing pills or taking them at the same time as certain medicines may make them less effective.

You can also take the combined pill as a tailored regime. This may include taking the pill for 21 days and stopping for 4, or taking the pill continuously without a break. For more information speak to a doctor or nurse. You can normally start taking the pill at any point in your menstrual cycle. There is special guidance if you have just had a baby, abortion or miscarriage. The guidance may also be different if you have a short menstrual cycle. Get advice from a doctor or nurse if you need it.

You may need to use additional contraception during your 1st days on the pill — this depends on when in your menstrual cycle you start taking it. If you start the combined pill on the 1st day of your period day 1 of your menstrual cycle you will be protected from pregnancy straight away. You will not need additional contraception. If you start the pill on the 5th day of your period or before, you will still be protected from pregnancy straight away.

You will not be protected from pregnancy straight away and will need additional contraception until you have taken the pill for 7 days. If you start the pill after the 5th day of your cycle, make sure you have not put yourself at risk of pregnancy since your last period. If you're worried you're pregnant when you start the pill, take a pregnancy test 3 weeks after the last time you had unprotected sex.

If you miss a pill or pills, or you start a pack late, this can make the pill less effective at preventing pregnancy.