Morning After Pill Side Effects: What to Expect
Quick Answer
Common side effects include nausea (14-23%), headache (10-17%), fatigue, and irregular bleeding. Most side effects are mild and resolve within 24-48 hours. Serious side effects are rare but include severe abdominal pain (may indicate ectopic pregnancy) which requires immediate medical attention.
Common Side Effects
Most people experience mild side effects that resolve on their own. Here's what clinical studies show:
Nausea (14-23%)
Headache (10-17%)
Fatigue (13-17%)
Abdominal pain (6-18%)
Dizziness (9-11%)
Breast tenderness (8-11%)
Irregular bleeding or spotting
Earlier or later next period
Managing Nausea
Nausea is the most commonly reported side effect. To reduce nausea:
- Take the pill with food
- Avoid taking on an empty stomach
- Rest after taking
- Stay hydrated
Important: If you vomit within 2 hours of taking levonorgestrel (or 3 hours for ulipristal acetate), you may need another dose. Contact your provider or our support team.
Changes to Your Period
Your next period may be:
- Earlier than expected - by a few days
- Later than expected - by up to 7 days
- Heavier or lighter than usual
- Different in duration
These changes are normal and your cycle should return to normal within 1-2 months.
When to take a pregnancy test: If your period is more than 7 days late, take a pregnancy test to confirm whether the EC worked.
When to Seek Medical Help
While rare, some symptoms require immediate medical attention:
- Severe abdominal or pelvic pain (may indicate ectopic pregnancy)
- Heavy bleeding (soaking more than 2 pads per hour for 2+ hours)
- Signs of allergic reaction (rash, difficulty breathing, swelling)
- Severe persistent vomiting
Long-Term Effects
Emergency contraception pills are considered safe for most people. Side effects are typically mild and temporary, including nausea, headache, and irregular bleeding. There are no known long-term health effects from using emergency contraception, even with repeated use. However, it should not replace regular contraception.
Emergency contraception:
- Does NOT affect future fertility
- Does NOT cause birth defects if pregnancy occurs
- Does NOT increase cancer risk
- Is safe to use multiple times if needed
Need emergency contraception? Get discreet delivery.
Order NowFrequently Asked Questions
Most side effects resolve within 24-48 hours. Menstrual changes may persist for 1-2 cycles before returning to normal.
Not everyone experiences side effects. Studies show nausea occurs in 14-23% of users, meaning most people don't experience significant nausea.
Side effect profiles are similar. Ulipristal acetate may cause a longer delay in your next period (up to 7 days vs a few days for levonorgestrel).
No. Side effects don't indicate whether the medication worked. The only way to confirm is waiting for your period or taking a pregnancy test if it's late.
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