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Micronor (Mini-Pill)

What is it?

The mini-pill is a progestin-only birth control pill. Other birth control pills have 2 types of hormone, progestin and estrogen. Progestin-only pills are a better option for people who are breastfeeding. At the Health Unit, the mini-pill is only offered to people who breastfeed.

If you start taking the pills after breastfeeding is well established (around 6 weeks after baby is born), the amount and quality of your breast milk should not change. You should also be able to breastfeed for as long as you wish.

Micronor can prevent pregnancy when it is taken exactly as prescribed.

How to take this medication:

If your baby is fully breastfed, you can start taking your pills 6 weeks after the birth of your baby.

If you have made an informed decision to offer some formula to your baby, you can start taking your pills 3 weeks after the birth of your baby.

  1. To begin taking your pills, start with the pill inside the red circle (where you see the word START).
  2. On the next day, take the next pill in the same row. Always follow the arrows from left to right (→).
  3. Take one pill AT THE SAME TIME EVERY DAY until the pack is empty. Your period should start during the last seven days of the pill pack. You must keep taking a pill every day, even when you are having your period.
  4. When you finish a pack of 28 pills, start another pack on the very next day. Do not wait any days between packs.

Do NOT take this medication if you:

Are having unusual vaginal bleeding (not your period).

Are a smoker and over age 35.

Have breast cancer or might have breast cancer.

Have tumors in your liver (cancerous or non-cancerous).

Have liver disease.

Have pre-diabetes or diabetes.

Are pregnant or think you might be pregnant.

Are allergic to norethindrone or to any other ingredients in Micronor.

Side effects:

The most common side effect of this medicine is a change in your menstrual bleeding (periods). Your periods might be early or late. You may also have some spotting in between periods.

Below is a list of serious side effects. Check with your health care provider right away if any of these happen to you:

  • Breast lumps
  • Depression
  • Severe headache
  • Missed menstrual period
  • Large amounts of bleeding and/or bleeding for a long time
  • Skin rash
  • Sudden or severe pain in your stomach or lower belly

Some less common side effects include:

  • Headaches
  • Sore breasts
  • Nausea
  • Vomiting
  • Diarrhea
  • Tiredness
  • Weight gain
  • Dizziness
  • Mood changes
  • Acne (pimples)
  • Extra hair on your face or body
  • Hair loss
  • Stomach pain or cramping

Drug interactions:

Some drugs can make birth control pills less effective or cause you to have break-through bleeding. Tell your health care provider if you take:

  • Drugs used to treat epilepsy (seizures)
  • Drugs used to treat TB (tuberculosis)
  • Drugs used to treat HIV/AIDS
  • Fosaprepitant (used to treat nausea)
  • Bosentan (used to treat high blood pressure)
  • Griseofulvin (an antifungal)
  • St. John’s wort (herbal supplement)
  • Sedatives and hypnotics (i.e. benzodiazepines, barbiturates, chloral hydrate, glutethimide, and meprobamate)

Missed dose:

If you are more than 3 HOURS LATE taking a pill:

  • Take the missed pill as soon as you remember. Your next pill should be taken at the regular time.
  • When you are late taking a pill, you could get pregnant. Use a backup method (condom) every time you have sex for the next 48 hours.
  • If you had sex without a condom at any time over the last 5 days, you could get pregnant. You may want to take emergency birth control to reduce the risk of pregnancy. Talk to your health care provider about emergency birth control options.


Store tablets at room temperature. Do not allow medication to freeze. Keep out of reach and sight of children.

Points to remember:

Progestin-only pills are less effective than birth control pills with estrogen added. This means you must be sure to take one pill at the same time every day. If you miss a pill at any time, you could get pregnant.

The biggest risks for getting pregnant are:

  1. When you start a new pack late, or
  2. When you are more than 3 hours late taking a pill or miss a pill completely.

To reduce the chances of getting pregnant, it is a good idea to also use another method of birth control, such as condoms or the lactational amenorrhea method (LAM).

Cigarette smoking can cause serious damage to your heart and blood vessels. If you are taking birth control pills you should not smoke.

Birth control pills DO NOT protect you from sexually transmitted infections (STIs). If you are at risk for STIs, it is recommended that you use a condom every time you have sex.