What is Emergency Contraception?

Even if you’re using protection, there’s always a chance that you could get pregnant. Perhaps you’ve turned to emergency contraception to avoid an unplanned pregnancy. But what happens if it fails? It’s important to understand your pregnancy options, so you can plan your next steps!

How Does Emergency Contraception Work?

Emergency contraception (also known as the Morning-After Pill) lowers the risk of pregnancy by preventing or delaying ovulation.

However, emergency contraception doesn’t always prevent ovulation,[1][2][3] but may also work by disrupting the hormonal environment and interfering with the embryo’s attachment to the uterus, resulting in its death.[4]

There are two common forms of emergency contraception: Progestin-only pill (Plan B One-Step®) and Ulipristal (ella®), a chemical cousin to mifepristone (part of the abortion pill protocol).[5][6]

How Effective is Emergency Contraception?

Plan B is most effective when taken as soon as possible after having unprotected sex. It is reported to reduce the risk of pregnancy for up to 72 hours, but is not always effective.[7] 

Ella can be taken up to five days after unprotected sex. However, research suggests that emergency contraception tends to be less effective in women with higher BMIs.[8] 

It’s also important to know that emergency contraception should not be used as a primary method of birth control.

What’s the Difference Between Emergency Contraception and the Abortion Pill? 

While they seem similar, Plan B and the abortion pill are not the same things. The difference is that Plan B aims to keep you from getting pregnant in the first place (and may disrupt a newly formed embryo from continuing to grow[9]), but the abortion pill is designed to end a pregnancy every single time it is used. 

If you have been sexually active in weeks prior to taking Plan B you may want to take a pregnancy test or even receive an ultrasound just to be certain that you’re not pregnant from a previous sexual encounter.

Can Plan B Cause Miscarriage?

A miscarriage is an unintended loss of a pregnancy before the 20th week of pregnancy. While the goal of Plan B is to prevent pregnancy altogether, if an embryo has already formed when Plan B is taken, it may interfere with the embryo’s ability to attach to the uterus, resulting in its death.[10] 

If that is not your intent, then Plan B may not be for you. 

Risks and Side Effects of Emergency Contraception

Common side effects of emergency contraception include[11]:

• Dizziness
• Headache
• Fatigue
• Cramps or abdominal pain 
• Nausea and/or vomiting
• Breast tenderness
• Delayed period (up to a week), heavier bleeding during your next period, or bleeding between periods

These side effects should be mild and only last a few days. However, if you experience significant lower abdominal pain after taking emergency contraception, contact your healthcare provider immediately to be evaluated for a possible ectopic pregnancy.

What to Do if Your Emergency Contraception Fails

If your period is delayed for more than three to four weeks, you may be pregnant.[12] Consider scheduling a free pregnancy test and free ultrasound at Cookeville Pregnancy Clinic! 

If your results come back positive, don’t panic. Our compassionate team is here to help you explore all of your pregnancy options so that you can make an informed and empowered decision! We will do everything we can to equip you to take your next steps with confidence!

Give us a call at (931) 526-5525 or make an appointment online today. All services are confidential and free of charge! 

Please be aware that Cookeville Pregnancy Clinic does not provide or refer for emergency contraception or abortion services. 

Sources

1. Hapangama D, Glasier AF, Baird DT. “The effects of peri-ovulatory administration of levonorgestrel on the menstrual cycle.” Contraception. 2001 Mar;63(3):123-9. DOI:10.1016/s0010-7824(01)00186-x https://www.contraceptionjournal.org/article/S0010-7824(01)00186-X/fulltext
2. Croxatto, HB, Brache V, Pavez M, Cochon L, Forcelledo ML, Alverez F, Massai R, Faundes A, and Salvatierra AM, 2004. “Pituitary-ovarian Function Following a Standard Levonorgestrel in Emergency Contraception Dose or a Single 0.75 mg Dose Given on the Days Preceding Ovulation.” Contraception. 2004 Dec;70(6):442-50. DOI:10.1016/j.contraception.2004.05.007 https://www.contraceptionjournal.org/article/S0010-7824(04)00156-8/fulltext
3. AAPLOG Committee Opinion #7. (2020, January). Embryocidal Potential of Modern Contraceptives. https://aaplog.org/wp-content/uploads/2024/05/Committee-Opinion-7-updated.pdf 
4. See source #3. 
5. Physician's Desk Reference. (2023, April 13). Ella Drug summary: Mechanism of action. https://www.pdr.net/drug-summary/?drugLabelId=1278
6. Saritha, F., Aiswarya, N., Aswath Kumar, R., & Dileep, K. V. (2023, February 3). Structural analysis and ensemble docking revealed the binding modes of selected progesterone receptor modulators. Journal of Biomolecular Structure & Dynamics. https://pubmed.ncbi.nlm.nih.gov/36752314/
7. Mayo Clinic. (2024, September 1). Levonorgestrel (Oral Route) Side Effects. https://www.mayoclinic.org/drugs-supplements/levonorgestrel-oral-route/side-effects/drg-20074413
8. Cleveland Clinic. (2022, July 1). Morning-After Pill: Emergency Contraception & Side Effects. https://my.clevelandclinic.org/health/treatments/23386-morning-after-pill
9. Kahlenborn, C., Peck, R., & Severs, W. B. (2015). Mechanism of action of Levonorgestrel emergency contraception. The Linacre Quarterly, 82(1), 18-33. https://doi.org/10.1179/2050854914y.0000000026
10. See source #9.
11. See source#8.
12. Mayo Foundation for Medical Education and Research. (2022, June 3). Morning-after pill. Mayo Clinic. https://www.mayoclinic.org/tests-procedures/morning-after-pill/about/pac-20394730#