Emergency contraception (EC) prevents pregnancy after unprotected sexual intercourse or when a regular contraceptive method fails. It works before pregnancy is established, primarily by preventing or delaying ovulation. EC methods prevent conception and do not terminate an existing pregnancy.
Understanding Emergency Contraception Options
Two types of emergency contraceptive pills are available: levonorgestrel-based pills (e.g., Plan B One-Step) and ulipristal acetate pills (Ella). Both work mainly by delaying or inhibiting ovulation, preventing an egg from being available for fertilization.
Levonorgestrel-based pills contain a synthetic hormone similar to progesterone. They are most effective when taken as soon as possible after unprotected sex. Ulipristal acetate is a progesterone receptor modulator that can delay ovulation even when the luteinizing hormone (LH) surge has already begun, making it effective closer to ovulation than levonorgestrel.
When and How to Take It
For levonorgestrel-based pills, a single 1.5 mg dose should be taken as soon as possible within 72 hours (three days) of unprotected intercourse. Some formulations involve two 0.75 mg doses taken 12 hours apart, though the single-dose option is common.
Ulipristal acetate (Ella) is taken as a single 30 mg tablet. This pill can be taken up to 120 hours (five days) after unprotected sex. Both types of pills can be taken with or without food.
If vomiting occurs within two hours of taking a levonorgestrel pill, or within three hours of taking ulipristal acetate, contact a healthcare provider. Another dose might be necessary if the medication was not fully absorbed. Anti-nausea medication can be taken beforehand if upset stomach is a concern.
What to Expect After Taking It
Temporary side effects are common after taking an emergency contraceptive pill. These can include headache, nausea, abdominal pain, fatigue, and breast tenderness. Symptoms are usually mild and subside within a day or two.
The menstrual cycle may change, with the next period potentially arriving earlier, later, lighter, or heavier. If a period is delayed by more than a week, or if pregnancy is a concern, take a pregnancy test. Severe abdominal pain, heavy bleeding, or continued absence of a period warrant medical attention. The morning-after pill prevents pregnancy; it does not end an existing one. If pregnancy occurs, it is not due to the pill failing to induce an abortion.
Accessing Emergency Contraception
Levonorgestrel-based emergency contraceptive pills are available over-the-counter without a prescription or age restrictions in the U.S. They can be purchased at most pharmacies, drug stores, and some convenience stores. Costs vary, but generic options are available at lower prices.
Ulipristal acetate requires a prescription from a healthcare provider. While there are no age restrictions, this requirement makes it less immediately accessible than over-the-counter options.