Emergency contraception (EC) is usually an afterthought but at Pandia Health, we want you to treat EC like a fire extinguisher. You want it when your emergency happens, sitting in the corner of your house. You don’t want to have to run to the pharmacy, worry if they have EC in stock, if it’s covered by your insurance, about transportation, and whether the pharmacist will give it to you. Like birth control, many don’t realize there is more than 1 option for EC and it isn’t a one size fits all. In this post, we’re breaking down the wild world of EC in hopes that women will have more piece of mind in what can be a stressful situation.

Did You Know There are 4 Types of Emergency Contraception?

That’s right! There’s more out there than Plan B! I bet that you and your doctor1 don’t know that the copper IUD is THE most effective form of EC and that Ella (ulipristal acetate) is the SECOND most effective form of EC and that Plan B and its generic equivalents are the THIRD most effective form of EC.  Lastly, the Yuzpe method of taking 100 mcg of ethinyl estradiol and 1 mg of norgestrel now and again in 12 hrs is the LEAST effective, but better than nothing if all you have is a pack of pills.

Forget Cuddling. Move, Move, Move!

EC can be used for up to 5 days after contraceptive failure or sexual assault but that doesn’t mean you should take your time. For pill forms, it’s best to take them ASAP. The copper IUD is equally effective throughout the 5 days. At Pandia Health, we recommend right away! If the condom breaks at 3am, I want that medicine in the woman’s mouth by 3:10. No cuddling, huddling, waiting for the “morning after.” ASAP. Get on it!

Literally Not A One Size Fits All

If your BMI is 30 or greater, if you use Plan B or its generic equivalents, then your have a 8x greater odds of getting pregnant compared to someone with a BMI of 25 or less2. You read that right! It’s literally not a one size (or weight) fits all.

Dr. Yen says: “If it were me or my daughter that needed EC, I would choose the copper IUD or Ella because of their greater efficacy at all time points and for those with BMI of 26 or greater.”

Here is Dr. Yen’s take on EC and BMI based on these 3 studies3

Your BMI Plan B (or generics) Ella Copper IUD
< 26 Up to 5 days, best ASAP Up to 5 days, best ASAP Same throughout 5 days, MOST effective
26-34 No efficacy, can try doubling up Up to 5 days, best ASAP Same throughout 5 days, MOST effective
35 or greater No efficacy, can try doubling up, consider copper IUD Lower efficacy, consider copper IUD Same throughout 5 days, MOST effective


Summary: copper IUD is best, then Ella, and then Plan B or its generics.

If your BMI is 26 or greater, consider IUD or Ella.

If your BMI is 35 or greater, best to go with copper IUD.

If you’ve got nothing else, then you could consider doubling up on your dose of Plan B if your BMI is 26 or greater.

“Another pharmacokinetic study (involving 32 women) similarly found that 24 hours after ingesting LNG serum concentration levels were 50% lower among obese-BMI women. Following use of UPA, however, blood levels were similar among obese-BMI and normal-BMI women.”4

(LNG = Plan B and its generics and UPA = Ella or ulipristal acetate)

Know the Law

Under the Affordable Care Act  there should be NO copay, no deductible for any FDA approved method of birth control – this includes the copper IUD, Ella, and Plan B and its generics (though harder to get for Plan B and generics because they are over the counter). If you have any problems getting it covered for NO copay, no deductible, contact https://nwlc.org/coverher/ and they will fight for you. National Women’s Law Center is a great advocacy organization.

Here’s our video on EC


This is THE trusted source by doctors about EC


and here is the LONG research document on the latest in EC, updated monthly by Princeton.


1 When I gave lectures to Stanford internal medicine residents in 2018, only 1 out of 60 resident physicians knew about the copper IUD and Ella and that they work better than Plan B and its generic equivalents. When I give lectures to doctors, most don’t know about Ella and the latest research about EC.

2 Festin MP, Peregoudov A, Seuc A, Kiarie J, Temmerman M. Effect of BMI and body weight on pregnancy rates with LNG as emergency contraception: analysis of four WHO HRP studies. Contraception. 2017;95:50-4.

3 Glasier A, Cameron ST, Blithe D, Scherrer B, Mathe H, Levy D, Gainer E, Ulmann A. Can we identify women at risk of pregnancy despite using emergency contraception? Data from randomized trials of ulipristal acetate and levonorgestrel. Contraception. 2011;84:363-7.

Moreau C, Trussell J. Results from pooled Phase III studies of ulipristal acetate for emergency contraception. Contraception. 2012;86:673-680.

Edelman A, Cherala G, Blue S, Erikson D, Jensen J. Impact of obesity on the pharmacokinetics of levonorgestrel-based emergency contraception: single and double dosing. Contraception. 2016 ;94:52-57.

4 Praditpan P, Hamouie A, Basaraba CN, Nadakumar R, Cremers S, Davis AR, Westhoff CL. Pharmacokinetics of levonorgestrel and ulipristal acetate emergency contraception in women with normal and obese body mass index. Contraception. 2017;95:464-9.

The views expressed in this article intend to inform and induce conversation. They are the views of the author and do not necessarily represent the views of Pandia Health, and are for informational purposes only, even if and to the extent that this article features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis or treatment, and should never be relied upon for specific medical advice.
reviewed by Dr. Yen 2.3.20