The MiniPill (progestin-only pill)

What Is It?

Pills contain the hormone progestin.

How Does It Work?

Thickens cervical mucus, blocking sperm. May or may not prevent ovulation. Prevents implantation of fertilized egg.

How Is It Used?

MiniPills are prescribed for women. A pill must be taken by mouth every day. The pill must be taken at the same time each day without interruption.

How Well Does It Work?

Typical use: 95%. Perfect use: 99.9%. Failure rate increased for women who take seizure medications. Use back-up method every time a pill is missed or taken late (even hours late).

What Are Its Main Advantages?

Reversible. Does not interfere with sex. Can be used by some women who cannot take regular birth control pills. Can be used with breastfeeding.

What Are Some Possible Problems?

Progestin-only methods often cause changes in menstruation including spotting, missed periods, irregular bleeding, heavy flow. Side effects: weight gain, headaches, breast tenderness, ovarian cysts.