Emergency Contraception (EC)

How many kinds of EC are there?


There are two hormonal methods of Emergency Contraception Pills available: progestin-only pills (Plan B) and combined estrogen and progestin pills (Yuzpe Regimen). In both methods, the pills are more effective the sooner they are taken, but they can be taken up to 120 hours (5 days) after unprotected vaginal intercourse.

Copper IUD

The copper IUD is an extremely effective form of emergency contraception if inserted within 5 - 7 days of unprotected intercourse (note: the Mirena cannot be used as an emergency contraceptive method).

The IUD prevents pregnancy by making the uterus inhospitable to sperm.

  • If the woman has not yet ovulated, (pre-ovulation), the IUD
    • prevents fertilization (the copper acts as an effective spermicide, destroying sperm)
  • If the woman has already ovulated (post-ovulation), the IUD
    • prevents implantation due to the uterine lining's disturbance at insertion.

When should EC be used?

EC can be used in cases of unprotected intercourse and method failure. Some instances where EC could be used are as follows:

  • When two or more consecutive oral contraceptives are forgotten (for POPS, when one pill is forgotten) and intercourse occurred without a backup method
  • When more than 14 weeks has passed since a previous Depo-Provera injection
  • When a condom has broken, slipped off, or leaked
  • When a diaphragm has failed (i.e., dislodged during intercourse, removed too early, found to be torn)
  • When the patch detaches or falls off for more than 48 hours and intercourse occurred without a backup method
  • When a NuvaRing has been out of the vagina for more than 3 hours and intercourse occurred without a backup method
  • When ejaculation has occurred inside the vagina while using the withdrawal method
  • When a woman had intercourse without using a birth control method
  • In instances of sexual assault
  • If a client requests it

Efficacy of emergency contraceptive methods


Method Risk Reduction
(if used within 120 hours)

Yuzpee Method


56% - 89%

Plan B

up 89%

Copper IUD 99.2%

Resources for more information

  • Options for Sexual Health clinics
  • The SEX SENSE Line at 1 800 SEX-SENSE or 604-731-7803 in the Lower Mainland.
  • If a client needs emergency contraception and the clinic is not open, she can:
    • call her family doctor
    • walk-in clinic
    • local pharmacy
    • check out the website http://ec.princeton.edu
    • go to the emergency room of a local hospital.