University Health Service


Emergency contraception can be used to prevent pregnancy within 120 hours (5 days) after unprotected vaginal sex. Some forms  are available without prescription. See How can I get EC?

On this page:

What is emergency contraception (EC)?

EC can be used to prevent pregnancy within 120 hours (5 days) after unprotected vaginal sex.

There are three main types of EC:

ParaGuard (copper IUD):

  • 99.9% effective up to 120 hours (5 days) after unprotected sex
  • Requires a prescription and a visit to a health care provider for insertion
  • Provides ongoing contraception for up to 10 years
  • Learn more about IUDs


  • 85% effective up to 120 hours after unprotected sex
  • Requires a prescription

Levonorgestrel (e.g. Plan B One-Step, Next Choice®, ...)

  • 89% effective up to 72 hours after unprotected sex; continues to reduce risk of pregnancy up to 120 hours but with decreasing effectiveness.
  • Are available without prescription (over-the-counter)

Emergency contraception pills:

  • Are not the "abortion pill" RU-486
  • Are not effective if you are already pregnant
  • Do not offer protection from sexually transmitted infections (STI)
  • Are not as effective as other hormonal contraception methods, so should not be your primary method of contraception. 
  • May not work if:
    • Ovulation has occurred
    • Too much time elapsed between unprotected sex and use of EC
    • You are already pregnant
  • May cause side effects including nausea, abdominal pain, fatigue, headache, menstrual changes

You might consider taking EC if:

  • You didn't use a condom or other reliable method of contraception
  • The condom broke or slipped off
  • Missed two or more combination birth control pills, or took the mini-pill more than 3 hours late this cycle
  • You were sexually assaulted and currently not using a reliable method of contraception (see the U-M Sexual Assault Survivor website for resources and information)

How can I get EC?

For ParaGard copper IUD:

  • Learn more about IUDs
  • Call UHS 734-764-8320, select option 2, and request "emergency contraception IUD"

By prescription (ella):  Call UHS 734-764-8320, select option 2, and request "ella emergency contraception." You can also get it in advance (you don't have to wait for an emergency to get it).

Without prescription: You can buy it at pharmacies, including the UHS Pharmacy, and other stores that sell medication. It can be purchased by both males and females of any age. There is no limit on the quantity that can be purchased at one time. 


At UHS, cost for over-the-counter EC is $40 (subject to change). If a clinic visit is needed, clinic visits are free for currently enrolled U-M students. Others pay fee-for-service or use billable insurance.

You should not use EC if:

  • You are pregnant, because it won't work and you will remain pregnant
  • You are allergic to any ingredients in the medication or device
  • You are breastfeeding (specifically not advised with ella)

How to take EC:

Take EC pills as soon as possible. Follow package directions. Eating a snack or drinking a glass of milk can help reduce nausea.

You should have a menstrual period within three weeks after EC. If you do not have your period within three weeks, you should have a pregnancy test. UHS provides Pregnancy Tests.

Begin using a reliable, routine method of contraception as soon as possible. Also remember to protect yourself from STI by using a condom each time you have sex.

Resources on EC:

Related resources from UHS: