The period of waiting after taking emergency contraception, such as Plan B One-Step, can be filled with uncertainty. While there are some expected hormonal effects, the most important indicator of its success is the arrival of your menstrual cycle. It's crucial to understand how the pill works and how to interpret your body's signals accurately.
How Plan B One-Step works
Plan B One-Step contains a high dose of the hormone levonorgestrel, which works primarily by temporarily delaying or preventing ovulation. By delaying the release of an egg from the ovary, it prevents the egg from being available for fertilization by sperm. It is important to note that Plan B is not an abortion pill and will not end an existing pregnancy.
Menstrual cycle changes and what they mean
The most significant sign that Plan B has worked is your next period beginning, but it may not arrive exactly as expected. The surge of hormones can temporarily throw your cycle off balance.
Expected variations in your next period
- Earlier than usual: A period that arrives a few days early can be a sign the pill worked, as your body is reacting to the hormonal shift.
- Later than usual: A slightly delayed period, sometimes up to a week, is a very common side effect and not necessarily cause for concern. If it is delayed by more than a week, a pregnancy test is recommended.
- Spotting: Many people experience light bleeding or spotting a few days or weeks after taking Plan B. This is a normal side effect of the hormonal changes and not your actual period.
- Heavier or lighter flow: The flow of your next period may be heavier, lighter, shorter, or longer than what is typical for you.
How to tell the difference between spotting and implantation bleeding
Spotting after taking Plan B can cause worry, but it is typically a harmless side effect. Implantation bleeding, on the other hand, is a potential early sign of pregnancy. Key differences include:
- Timing: Spotting from Plan B can happen anytime between taking the pill and your next period. Implantation bleeding occurs about 6-12 days after conception.
- Duration and flow: Spotting from Plan B is typically light and lasts a few days at most. Implantation bleeding is often described as very light, short-lived, and not enough to fill a pad or tampon.
Common side effects after taking Plan B
Experiencing side effects does not confirm that the pill was successful, nor does a lack of side effects mean it failed. Most side effects are mild and resolve within a day or two.
Timeline of typical side effects
Day 1-2
- Nausea: A common symptom, but if you vomit within two hours of taking Plan B, you may need to take another dose.
- Fatigue: Feeling tired is a normal response to the high hormone dose.
- Headache and dizziness: Mild headaches and dizzy spells can occur.
- Breast tenderness: Similar to PMS symptoms, breast tenderness is possible.
Days or weeks later
- Menstrual changes: Spotting, and changes to your next period's timing and flow are expected.
Confirmatory signs that Plan B worked
While monitoring your period and side effects can provide clues, only two things can reliably confirm that Plan B was effective.
- Your next period arrives: The most reassuring sign is the arrival of your next period, whether it's early, late, or on time.
- Negative pregnancy test: If your period is delayed by more than a week, taking a home pregnancy test is recommended. A negative result provides strong confirmation that the pill was successful. For the most accurate results, wait at least three weeks after unprotected sex or until a week after your missed period.
When to contact a healthcare provider
While most side effects are harmless, certain symptoms warrant contacting a doctor for advice.
- Severe abdominal pain: Intense pain, especially if it occurs 3-5 weeks after taking the pill, could be a sign of a serious condition like an ectopic pregnancy.
- Excessive bleeding: Soaking through more than one pad or tampon in an hour for several hours is a red flag.
- Vomiting: If vomiting occurs within two hours of taking the pill, another dose is needed. A healthcare provider can advise on the best course of action.
- Persistent or worsening symptoms: Side effects that don't go away after a couple of days or get worse should be evaluated by a professional.
Comparison: Plan B versus Ella
| Feature | Plan B One-Step (Levonorgestrel) | Ella (Ulipristal Acetate) |
|---|---|---|
| Mechanism | Delays or prevents ovulation. | Delays or prevents ovulation, also affects uterine lining. |
| Window | Up to 72 hours (3 days) after unprotected sex. | Up to 120 hours (5 days) after unprotected sex. |
| Effectiveness | Up to 89% effective within 72 hours. | 98% effective within 72 hours, higher than Plan B in this window. |
| Weight | Less effective for those over 165 lbs (75 kg). | More effective for those over 165 lbs; effectiveness decreases over 195 lbs. |
| Availability | Over-the-counter without age restriction or ID. | Prescription only. |
| Cost | Typically around $40-$50. | Varies, often more expensive than Plan B. |
Conclusion
While the anxiety after taking Plan B is natural, remember that the most reliable confirmation of its success is your next menstrual period arriving. While side effects like menstrual changes, nausea, or headaches may occur, they are not definitive proof of effectiveness. If your period is more than a week late, the most reliable course of action is to take a home pregnancy test. If you experience severe symptoms or have ongoing concerns, consulting a healthcare professional is always the best step to take for your health and peace of mind. It is also wise to consider more reliable, long-term contraception if you find yourself frequently using emergency contraception.
