Ella vs Plan B: Which Works Better?
If you’re standing in the pharmacy aisle or frantically searching online after unprotected sex, one question usually comes first: Ella vs Plan B: Which works better? The answer depends on when you had sex, where you are in your menstrual cycle, your body weight, and how quickly you can get treatment.
Both are emergency contraception. Both are designed to reduce the chance of pregnancy after unprotected sex or birth control failure. But they are not the same medication, and choosing the right one can make a real difference.
Ella vs Plan B: What’s the difference?
The biggest difference is how they work.
Plan B contains levonorgestrel, a synthetic form of progesterone. It works mainly by delaying or preventing ovulation before an egg is released.
Ella contains ulipristal acetate, which also works by delaying ovulation, but it does so differently. It can continue delaying ovulation even when your body is closer to releasing an egg. That is one reason many experts consider Ella the more effective emergency contraceptive overall.
Neither medication ends an existing pregnancy, and neither works like the abortion pill.
Which works better?
For many women, Ella is more effective than Plan B.
That is especially true if:
- It has been several days since unprotected sex.
- You are closer to ovulation.
- You have a higher body weight.
- You want the option with the highest overall effectiveness.
Plan B works best when taken as soon as possible after unprotected sex, ideally within 72 hours. Although it may still provide some benefit up to five days afterward, its effectiveness decreases over time.
Ella remains effective for up to five days after unprotected sex and tends to maintain its effectiveness more consistently throughout that window.
If timing is close and both medications are available, many clinicians prefer Ella.
Learn more about how ella works and when you should take ella.
Does timing matter?
Absolutely.
Emergency contraception is a race against ovulation.
If ovulation has already happened, neither Ella nor Plan B works as well because both medications work mainly by preventing or delaying the release of an egg.
That is why acting quickly matters.
Waiting another day while trying to decide between medications can sometimes have a bigger impact than the difference between the medications themselves.
If you’re unsure where you are in your cycle, don’t wait for certainty before seeking care.
What if you’re close to ovulation?
This is where Ella usually has the advantage.
Research suggests Ella continues working closer to ovulation than levonorgestrel emergency contraception.
That does not mean it works after ovulation has already occurred, but it may remain effective later into the fertile window than Plan B.
If you’re worried you may already be ovulating, you may also want to read:
- Does Plan B work after ovulation?
- Can Ella work after ovulation?
- Why doesn’t Ella work after ovulation?
Does body weight matter?
It can.
Evidence suggests levonorgestrel emergency contraception may become less effective as body weight or BMI increases.
Ella appears to maintain effectiveness better in women with higher body weights, although no emergency contraceptive is perfect.
If weight is part of your decision, discuss it with a clinician rather than assuming one medication is automatically right for you.
You can also learn more about Ella for higher body weight.
Can you take birth control right after Ella?
No—not immediately.
One important difference between Ella and Plan B is what happens afterward.
After taking Ella, you should generally wait 5 days before starting or restarting hormonal birth control because hormones may reduce how well Ella works.
Plan B does not have the same waiting recommendation.
This is one of the biggest areas where women receive conflicting advice online.
What side effects are different?
Fortunately, both medications have similar side-effect profiles.
Common side effects include:
- Nausea
- Headache
- Fatigue
- Breast tenderness
- Abdominal discomfort
- Changes in your next menstrual period
Your next period may come earlier, later, lighter, or heavier than usual after either medication.
If you’re wondering what to expect afterward, read:
Can you take them more than once?
This is another area where myths spread quickly.
Taking emergency contraception more than once in the same cycle is sometimes medically appropriate, but it depends on the situation.
That does not mean it should become your regular birth control method.
If you find yourself needing emergency contraception repeatedly, it may be worth discussing an ongoing birth control option that better fits your needs.
Learn more about:
So which one should you choose?
If you have access to both medications and are medically eligible, Ella is often the preferred choice because it generally maintains better effectiveness throughout the five-day treatment window and may perform better closer to ovulation.
Plan B is still an effective option, especially when taken as soon as possible after unprotected sex.
The “best” emergency contraception is often the one you can get quickly without unnecessary delays.
If you’re unsure which medication fits your situation, a licensed clinician can review your timing, cycle, medical history, and medications to help you choose.
The bottom line
When comparing Ella vs Plan B: Which Works Better?, the answer is that Ella is generally considered the more effective oral emergency contraceptive, particularly later in the five-day window and closer to ovulation.
That does not mean Plan B is ineffective. It has helped prevent countless unintended pregnancies and remains an important option.
The key is acting quickly, understanding the differences, and choosing the medication that best fits your situation rather than relying on myths or internet guesses.
If you need emergency contraception now, you can start your emergency contraception visit here.