Ella for Emergency Contraception

Morning-after pill on a neutral background
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Ella was approved as emergency contraception by the FDA in August 2010. Ella consists of just one oral pill (ulipristal acetate, 30 mg). Ella can be used by women to prevent an unintended pregnancy after unprotected sex or contraceptive failure with just one pill that can be taken immediately.

Ella is most effective if taken right away, but it can be used for up to 120 hours (5 days) after unprotected sex.

Other emergency contraception options, Plan B One-Step, Next Choice One Dose, My Way, Take Action, and Next Choice, are FDA-approved to be used up to 72 hours (3 days) after contraceptive failure or unprotected intercourse.


Ella is thought to work for emergency contraception primarily by stopping or delaying the release of an egg from the ovary, so no egg will be available for a sperm to fertilize.

It is possible that Ella may also work by preventing attachment (implantation) to the uterus. Though Ella prevents ovulation for as long as 5 days after unprotected sex, there is some concern that women may mistakenly believe that once taking Ella, it can further protect them against pregnancy from any additional acts of unprotected sex for 5 days. This is not the case, as sperm from additional sex can outlive the initial 5-day window.

Ella contains ulipristal, a non-hormonal drug that blocks the effects of key hormones necessary for conception.

Ella belongs to a class of drugs called selective progesterone receptor modulators. The only other approved drug in this class is mifepristone, better known as RU-486. Mifepristone is approved for use as part of a regimen that induces abortion.

Because it is better absorbed by the body than mifepristone, Ella can be used at low doses that prevent conception but that should not cause abortion. It remains unclear, though, whether Ella might increase the rate of spontaneous abortion in the few women who become pregnant despite using the drug.

There is also confusion as to whether or not Ella may cause harm to an existing pregnancy (if the woman is actually pregnant when taking Ella).

What It Is Not

Emergency contraception is often mistakenly confused with the early abortion pill, RU486 (also referred to as M&M, Mifeprex, mifepristone or medical abortion). These two medications serve two different purposes and work completely differently from one another.

Ella is not an abortion pill. It is not effective if taken after a woman is already pregnant.

According to Watson Pharmaceuticals, the manufacturer of this emergency contraceptive, Ella is not for use to end an existing pregnancy.

When to Use

To reduce the risk of an unplanned pregnancy, Ella should be taken as soon as possible within 120 hours (5 days) of unprotected sex or contraceptive failure. The sooner Ella is taken, the more effective it'll be.

Ella can also be used any time during your menstrual cycle and can be taken with or without food.

If you vomit within 3 hours of taking the pill, you should immediately contact your doctor to discuss whether to take another pill.

Who Should Not Use It

Ella is not intended to be used as a substitute for routine contraception use—it does not work as well as most other forms of birth control when they are used consistently and correctly.

You should not use Ella more than one time in the same menstrual cycle for different acts of unprotected sex or birth control failure.

Do not take Ella if you know or suspect you are already pregnant. If there is a chance you could already be pregnant, your doctor should provide you with a pregnancy test before prescribing Ella. The risks to a fetus when Ella is administered to a pregnant woman are unknown.

Side Effects

When used as directed, Ella is safe for most women. The most common side effects reported during clinical trials of 2,637 women receiving Ella included:

  • Headache (18%)
  • Nausea (12%)
  • Abdominal and upper abdominal pain (12%)
  • Dysmenorrhea (uterine pain during menstruation) (10%)
  • Fatigue (6%)
  • Dizziness (5%)

After taking Ella, you could likely experience changes in your period. In some cases, your next period may be heavier or lighter, or earlier or later.

It is important to consult a doctor if your scheduled period is more than 1 week late, as this may indicate that pregnancy could have occurred.

If you are experiencing severe abdominal pain 3 to 5 weeks after taking Ella, there could be the possibility that you're having an ectopic pregnancy, so you should seek immediate medical attention.


Ella is most effective the sooner it is started. When taken as directed (within 120 hours of unprotected sex or contraceptive failure), Ella will reduce the chance that you will get pregnant.

Ella is not effective in every case and is only to be used for a single episode of unprotected intercourse. During clinical trials, Ella significantly reduced the pregnancy rate from an expected rate of 5.5% (the number of pregnancies expected without emergency contraception calculated based on the timing of intercourse with regard to each woman’s menstrual cycle) to an observed rate of 2.2%.

Ella appears to be less effective in obese women. During clinical trials, 3.2% of women with a body mass index (BMI) > 30 kg/m became pregnant using Ella.

Ella will not continue to prevent pregnancy during the rest of a woman’s cycle, so make sure that you use a regular birth control method the next time you have sex.

The manufacturer states that "a rapid return of fertility is likely following treatment with Ella for emergency contraception; therefore, routine contraception should be continued or initiated as soon as possible following use of Ella to ensure ongoing prevention of pregnancy."

Certain medications and herbal products could also decrease the effectiveness of Ella. These include:

  • Barbiturates
  • Bosentan
  • Carbamazepine
  • Felbamate
  • Griseofulvin
  • Oxcarbazepine
  • Phenytoin
  • Rifampin
  • St. John’s Wort
  • Topiramate


Talk to your healthcare provider if you use hormonal birth control (like the pill, the patch, Depo Provera, NuvaRing).

Using Ella may make your regular hormonal birth control method less effective. If you use Ella as an emergency contraceptive, you should use a reliable barrier method of birth control (such as a condom with spermicide, female condom, sponge) during any other times that you have sex in that same menstrual cycle.

Depending on your healthcare provider, you may or may not need an office visit in order to receive an Ella prescription. The manufacturer advises medical providers to confirm or rule out an existing pregnancy before writing a prescription for Ella.

As a precaution, you can ask your doctor about obtaining a prescription for Ella to have ahead of time—just in case an emergency occurs. This way, you will already have a prescription to be filled immediately and will not need to wait to get a medical appointment.


Prices for this morning-after pill vary depending on where you purchase it. Ella may cost at least $55 at the pharmacy. There is an online prescription service that you can use to purchase Ella for $67, plus free shipping and handling for next-day delivery. 

STI Protection

Ella offers no protection against sexually transmitted infections or HIV.

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Article Sources

  • Watson Pharmaceuticals. Ella - ulipristal acetate tablet: Complete Prescribing Information.