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CHAPTER 1 - Combined Oral Contraceptives
What Are Combined Oral Contraceptives?
- Pills that contain low doses of 2 hormones—a progestin and an estrogen—like the natural hormones progesterone and estrogen in a woman’s body.
- Combined oral contraceptives (COCs) are also called “the Pill,” low-dose combined pills, OCPs, and OCs.
- Work primarily by preventing the release of eggs from the ovaries (ovulation).
Effectiveness depends on the user: Risk of pregnancy is greatest when a woman starts a new pill pack 3 or more days late, or misses 3 or more pills near the beginning or end of a pill pack.
- As commonly used, about 7 pregnancies per 100 women using COCs over the first year. This means that 93 of every 100 women using COCs will not become pregnant.
- When no pill-taking mistakes are made, less than 1 pregnancy per 100 women using COCs over the first year (3 per 1,000 women).
Return of fertility after COCs are stopped: No delay
Protection against sexually transmitted infections (STIs): None