Ella is a prescription morning-after pill that's more effective than Plan B - here's how to decide if it's right for you

• Ella is a non-hormonal morning-after pill that reduces your chance of pregnancy by 85%.
• Ella must be taken within five days of unprotected sex and is only available via prescription.
• However, it may be less effective if you weigh more than 195 pounds or have a BMI of 35 or more.

Emergency contraception is a safe and often reliable way to prevent unwanted pregnancies. When considering your options, there are a variety of methods to choose from, including Ella, a prescription morning after pill.

Here is all you need to know about Ella and whether it's right for you.

What is Ella?

Ella is an emergency contraception pill that contains a non-hormonal drug called ulipristal acetate.

It works as an antiprogestin, which prevents pregnancy after unprotected sex by blocking the production of the hormone progesterone. This either stops ovulation - when the egg releases from the ovary - or prevents the egg from attaching to the wall of the uterus.

Ella can be an effective form of emergency contraception if taken within five days (120 hours) of unprotected sex, reducing your chances of pregnancy by 85%.

Ella differs from other morning-after pills, like Plan B, because it does not contain the hormone levonorgestrel. Levonorgestrel pills are only effective for three days (72 hours) after sex and are generally less effective than Ella.

Is Ella right for me?

There are some factors to consider before choosing Ella as your emergency contraception option.

You need a prescription. In order to take Ella, you will need a prescription from your doctor, nurse, or gynecologist. There are some online prescription services you can order from as well.

Cost and accessibility. While Ella is generally widely available throughout the US, not all states or towns may have the same accessibility as others, says Julie Levitt, MD, a gynecologist at The Women's Group of Northwestern.

The cost can vary, as well. Most insurance plans, including Medicaid, cover prescription contraception, but if you are unsure, speak with your doctor or the pharmacist to see if you are covered. Without insurance, the cost is around $50, but coupon programs such as GoodRx can lower the price.

Time. Ella is only effective for five days (120 hours) from when you last had unprotected sex.

Weight. Ella may be less effective as an emergency contraceptive if you weigh more than 195 lbs or if you have a BMI of 35 or more.

Interactions with other medication. There are some medicines that will impact the effectiveness of Ella, including:

• Certain HIV/AIDS medications
• Rifampin (an antibiotic)
• Fungal infection medication such as griseofulvin
• Certain Epilepsy and seizure medication like Phenobarbital or Primidone
• St. John's Wort, which can be used for depression, ADHD, or other disorders.

If you are uncertain about the effect Ella will have with another medication you are taking, speak to your doctor, nurse, or another healthcare provider.

How to use Ella

Ella is a single pill that you use once after unprotected sex. If you vomit within three hours after taking it, you may have to take the pill again, but check with your medical provider.

Unlike hormonal emergency contraception like Plan B, Ella does not diminish in effectiveness over time.

"It is supposed to maintain its effectiveness from day one to day five," says Kelly Fitzgerald, NP, a nurse practitioner at Rush University Medical Center. "But you should still take the pill as soon as you can to avoid any chance of ovulation."

Important: Fitzgerald also recommends not taking your daily birth control within five days after taking Ella. Birth control, which contains the hormone progestin, could interfere with the antiprogestin effect in ulipristal acetate and stop Ella from preventing the pregnancy.

Ella side effects

After taking Ella, there may be some side effects, but they are not very common and do not last long, according to Levitt. Some may experience:

• Nausea
• Dizziness
• Headache
• Stomach or menstrual pain

People who take Ella may also experience a disruption or delay in their period, says Fitzgerald.

But not everyone is going to react to the pill the same way. For others, Ella may not impact their period at all. If your period is delayed more than a week, you may want to consult your doctor or take a pregnancy test.

Insider's takeaway

Ella is a non-hormonal emergency contraceptive "day after" pill that will prevent unwanted pregnancy for up to five days after unprotected sex.

You will need a prescription for Ella and the product may not be as widely available as other emergency contraceptives, but the pill does not diminish in effectiveness from day one to day five and side effects are uncommon.

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