This chapter on progestin-only pills focuses on breastfeeding women. Women who are not breastfeeding also can use progestin-only pills. Guidance that differs for women who are not breastfeeding is noted.

Key Points for Providers and Clients
  • Take one pill every day. No breaks between packs.
  • Safe for breastfeeding women and their babies. Progestin-only pills do not affect milk production.
  • Add to the contraceptive effect of breastfeeding. Together, they provide effective pregnancy protection.
  • Bleeding changes are common but not harmful. Typically, pills lengthen how long breastfeeding women have no monthly bleeding. For women having monthly bleeding, frequent or irregular bleeding is common.
  • Can be given to a woman at any time to start now or later.

What Are Progestin-Only Pills?

  • Pills that contain very low doses of a progestin like the natural hormone progesterone in a woman’s body.
  • Do not contain estrogen, and so can be used throughout breastfeeding and by women who cannot use methods with estrogen.
  • Progestin-only pills (POPs) are also called “minipills” and progestin-only oral contraceptives.
  • Work primarily by:
    • Thickening cervical mucus (this blocks sperm from meeting an egg)
    • Disrupting the menstrual cycle, including preventing the release of eggs from the ovaries (ovulation)

How Effective?

Effectiveness depends on the user: For women who have monthly bleeding, risk of pregnancy is greatest if pills are taken late or missed completely.

Breastfeeding women:

  • As commonly used, about 1 pregnancy per 100 women using POPs over the first year. This means that 99 of every 100 women will not become pregnant.
  • When pills are taken every day, less than 1 pregnancy per 100 women using POPs over the first year (3 per 1,000 women).

Less effective for women not breastfeeding:

  • As commonly used, about 7 pregnancies per 100 women using POPs over the first year. This means that 93 of every 100 women will not become pregnant.

  • When pills are taken every day at the same time, less than 1 pregnancy per 100 women using POPs over the first year (3 per 1,000 women).

Return of fertility after POPs are stopped: No delay

Protection against sexually transmitted infections (STIs): None

Why Some Women Say They
Like Progestin-Only Pills
  • Can be used while breastfeeding
  • Can be stopped at any time without a provider's help
  • Do not interfere with sex
  • Are controlled by the woman

Progestin-Only Pills, Single Pill Pack