The Birth Control Pill

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What is the pill?

The pill is a hormonal birth control method that you get by prescription from your health care provider.

How does it work?

In a normal cycle, hormones cause the ovaries to release an egg about once a month. The birth control pill is an artificial form of these hormones. They prevent pregnancy by stopping the ovaries from releasing eggs. They also cause mucus in the cervix to thicken making it hard for sperm to enter the uterus. The pill can also cause the lining of the uterus to get thinner making it hard for the fertilized egg to attach.

How effective is it?

The pill is 99.9 per cent effective in preventing pregnancy if you use it correctly all the time. With typical use it is 92 to 97 per cent effective. The pill does not protect against sexually transmitted infections (STIs). You need to use condoms every time you have sex to help protect you from STIs.

How do I use the pill?

• Start the pill as directed by your health care provider. Usually you start taking the pill on the first day of your cycle or the first Sunday after your period begins.

Note: If you don’t start the pill within five days of the start of your period, you will need to use a backup method of birth control for seven days.

• The pill is available in packages of 21 or 28 or 92. When you get your package, make sure you read the information provided, check the expiry date and take the pill at the same time each day.
• For 21-day pack, take one pill each day for 21 days and then stop for seven days. Start a new package after seven pill-free days, no matter when your priod begins or ends. This is important to reduce your risk of pregnancy.
• For 28-day package, you take one pill every day. Do not take a break before starting the next package. 
• For 92-day package, refer to the product insert or the extended or continuous use fact sheet.

What do I do if I miss pills?

• If you miss one active pill by less than 24 hours in any week, you should take it as soon as you remember. This may mean taking two pills in one day.
• During week one:
  • If you miss one or more active pills by more than 24 hours, take one pill immediately and one pill daily until the end of the cycle and use condoms. If you had unprotected sex within five days of missing your pill call the Sexual Health Clinic, your health care provider or a pharmacists to discuss the need for the emergency contraceptive pill (ECP).
• During week two or three:
  • If you miss one or two active pills take one pill immediately and one pill daily until the end of the cycle. Discard any placebo pills and start a new pack without a break. Use condoms for seven days.
  • If you miss three or more active pills, take one pill immediately and one pill daily until the end of the cycle. Discard any placebo pills and start a new pack without a break. Use condoms for seven days. If you have unprotected sex within five days of missing your pills, contact the Sexual Health Clinic, your health care provider or a pharmacist about the need for the emergency contraceptive pill (ECP).

Are there times when the pill may not be effective?

Yes. Many prescription, non-prescription and herbal medicines may interfere with the pill. Always check with the Sexual Health Clinic, your health care provider or a pharmacist before taking another medication.

Note: You may need to use a backup method of birth control while you are on the medication and for seven days afterwards.

• If you throw up within one hour of taking your pill, take a replacement pill from another package or contact the Sexual Health Clinic, your health care provider or a pharmacist for a replacement pill.
• If you have severe diarrhea or vomiting for two or more days continue taking your pills if you can and use a backup method of birth control for the next seven days.

If you have unprotected sex during a time when the pill may not be effective, contact the Sexual Health Clinic, your healthcare provider or a pharmacist about the need for emergency contraception (ECP).

What are the advantages to using the pill?

You may notice lighter and shorter periods and a more regular cycle. You may also experience less menstrual cramping and less acne.

Some benefits occur the longer you are on the pill, such as decreased risk of:

• cancer of the ovaries or lining of the uterus
• pelvic inflammatory disease and endometriosis
• cysts in the ovaries and breasts
• tubal pregnancy
• anemia from low iron levels.

What are the side effects or possible complications of taking the pill?

Side effects from the pill most often occur in the first three months of use. Unless the side-effects are severe, it is recommended to take the pill for three months before you think about a change in pills.

Some of the possible side effects:

• spotting or bleeding between periods
• missing a period
• nausea or an upset stomach. Taking the pill at bedtime or with food may reduce these symptoms.
• tender breasts, fluid retention, headaches or moodiness.

Serious side effects are rare, but there is a risk of blood clots, stroke or heart attack with any hormonal contraception.

Seek medical attention right away if you notice any of the following:

• severe pain in your legs or abdomen
• severe chest pain, cough or shortness of breath
• blurring or loss of vision, speech problems
• breast lump
• depression or jaundice (yellowing of the skin).

Will I gain weight on the pill?

Many women are concerned about weight gain. Many pills are now much lower in hormones than they were in the past. Studies have shown that there is no significant weight gain in women on the pill. Sometimes during the first few months on the pill you may have an increased appetite. It is important to make sure that you are eating healthy and are physically active. If you have concerns, call the Sexual Health Clinic, your health care provider or a pharmacist.

What else do I need to know?

• It is important to have a yearly physical, while you are on the pill.
• Women who use hormonal contraceptives are strongly advised not to smoke. Cigarette smoking can increase the risk of high blood pressure, heart disease and blood clots. The risk increases with age.
• Women who smoke need to stop using the pill by age 35 due to an increased risk of heart disease.