Emergency Contraception

Description
  • Emergency contraception (EC) – use of a drug or device to prevent unplanned pregnancies after unprotected sexual intercourse (UPSI)
  • Intended for occasional use as a back-up in case of failure of regular method of contraception
  • Not recommended as a primary contraceptive method – less effective than regular hormonal contraception for this purpose
Indications for ECP
  • Unprotected sexual intercourse (UPSI) defined as:
    • No contraceptive method used
    • Condom slip or breakage
    • Incorrect use of regular contraceptive method
      • > 2 oral contraceptive tablets missed any time during cycle, 1 tablet missed in the first week, >7-day pill-free interval
        • Decreased absorption is a concern if vomiting and/or diarrhea for > 48 h
      • Removed intravaginal contraceptive ring for >3 hours during an in-ring week
      • Removed transdermal contraceptive patch for >1 hour during a patch week
      • > 13-week interval between depo-medroxyprogesterone injections
    • Ejaculation on external genitalia
    • Sexual assault
  • Ovulation times can vary between women, between cycles in individual woman
    • Any UPSI has some risk of pregnancy
When to Refer

Note, there are no medical contraindications for oral hormonal emergency contraception (EC) other than allergy to components of EC products

  • If menstrual period is overdue, recommend a pregnancy test; if positive refer
  • If patient chooses a copper-IUD for EC after being informed about various EC methods, refer. If uncertain patient will be able to have the IUD inserted within 7 days of UPSI, provide oral EC
Treatment

1) Devices for EC

2) Pharmacologic agents for EC

A) Levonorgestrel (LNG)

    • In Saskatchewan, currently Schedule II status
    • Mechanism of Action: Delays ovulation by preventing luteinizing hormone surge that triggers ovulation
    • Not effective the day before ovulation or after ovulation has occurred
    • Overall, reduces risk of pregnancy by 50 %
    • Dose: 1.5 mg PO stat (available in 0.75 mg and 1.5 mg tablets) within 3 days of UPSI
      • Most effective if taken within 24 hrs of UPSI, protective effect gradually decreases
    • Hormonal contraception can be started the day of or the day after LNG; abstinence or barrier method of contraception is required for the next 7 days
    • Effect dependent on patient weight - Health Canada Advisory
      • Possibly lowered effect if BMI 25 – 29 (wt > 75 to 80 kg)
      • May be ineffective if BMI > 30  (wt > 80 kg)
      • Don’t withhold treatment but ensure patients with BMIs > 25 are aware of the increased risk and alternative EC options.
      • Can be repeated as often as required for UPSI incidents

 B) Ulipristal acetate

    • Schedule I, may be prescribed by pharmacist with ECP training
    • Mechanism of action: progesterone receptor modulator
      • Delays ovulation
      • Direct inhibitory effect on follicular rupture, even when given shortly before ovulation
      • Not effective if ovulation has occurred
      • Reduces risk of pregnancy by approximately 64 %
      • Effectiveness remains relatively consistent over 5 day window
    • More effective than LNG, especially days 4 & 5 post-UPSI
    • More effective than LNG in overweight and obese women (although some studies indicate reduced effect compared with normal weight women); no information on effectiveness in patients with BMI > 35
    • Dose: 30 mg PO stat within 5 days of UPSI
      • Not recommended for use more than once during same menstrual cycle

 C) Yuzpe Method

    • Older method, not widely used any more
    • Less effective (37%),  higher incidence of side effects due to estrogen component
    • Two doses (q 12 hours) of various combined oral contraceptives (See Table 1 below)
    • Similar concerns as with levonorgestrel EC in regards to reduced effectiveness in overweight women

    • Table 1: Yuzpe method dosing
      Product Tabs / dose

      Ethinyl estradiol / levonorgestrel 
      mcg/dose

      Alesse®,  Alysena™, Esme, Lutera™

      5 100/500

      Triquilar®

      4 yellow 120/500

      Min-Ovral®, Portia®, Ovima™

      4 120/500

 

3) EC Drug Interactions:

  • Hormonal contraception (HC)
    • Levonorgestrel: HC can be started the day of or the day after EC; abstinence or barrier method of contraception required for 7 days for combined hormonal products, 2 days for progestin-only product
    • Ulipristal acetate: Wait 5 or more days before starting HC; abstinence or barrier method of contraception required for 14 days
    • Ulipristal acetate + levonorgestrel (and Yuzpe products)
      • Theoretical antagonism of effect. Not recommended for use together or within same menstrual cycle
    • Enzyme inducing drugs, natural products such as carbamazepine, modafinil, phenytoin, protease inhibitors, phenobarbital, St. John's wort, topiramate
      • Decreased efficacy of levonorgestrel, Yuzpe regimen, ulipristal acetate
      • Copper IUD is method of choice: not affected by interaction
      • Do not withhold hormonal EC but recommend patients consider the copper IUD in addition to oral EC 

4) Adverse Effects:

  • Nausea and vomiting
    • Higher incidence with Yuzpe method products; incidence lower with levonorgestrel and ulipristal acetate
    • Dose should be repeated if patient vomits within 2 hours
    • If using Yuzpe regimen, recommend dimenhydrinate prior to dose of EC
  • Dizziness
  • Fatigue
  • Headache
  • Breast tenderness
  • Lower abdominal pain
  • Spotting, breakthrough bleeding
  • Effects usually resolve within 24 hours

5) Lactation

  • Levonorgestrel 1.5 mg is oral EC of choice
    • No interruption of breastfeeding required 
  • Ulipristal acetate
    • No information is available on use during breastfeeding
    • Pump and dump for 24 hrs (CDC), 1 week (WHO) after ulipristal acetate administration

6) Comparison of methods

Emergency Contraception

Pregnancies/1000 UPSI*

Access

Cost**

None

80

-

-

Yuzpe

20

Schedule I

$8 – 16***

Levonorgestrel

10

Schedule III (NAPRA)

$14 – 18

Ulipristal acetate

5

Schedule I

$27

Copper IUD

< 1

Medical device
Insertion by physician, trained healthcare provider

$52 - 186

*UPSI = unprotected sexual intercourse
** Acquisition cost as of December 2015
*** Cost based on one pack of oral contraceptive

General Advice / Monitoring
  • Education:
    • Mechanism of action
    • Effectiveness
      • Copper IUD most effective method at any time during cycle
      • Compare risk of pregnancy with and without EC
    • Does not protect against sexually transmitted infections
      • If symptomatic or symptoms emerge, advise visit to STI clinic, MD or NP
    • Does not provide ongoing protection against pregnancy
      • Abstinence or use of barrier methods after ECP
      • Discuss regular contraceptive methods and provide or refer as appropriate
  • Menstruation should occur within 21 days
    • Pregnancy test and/or refer if > than 21 days
  • Administration instructions
    • When to start / continue regular hormonal contraceptive
    • How long to use alternate contraceptive methods (abstinence, barrier methods)            
  • Adverse effects management
    • Nausea: Take with food, or take dimenhydrinate as pre-med (with Yuzpe regimen)
    • Vomiting: Repeat dose if vomit within 1 to 2 hours
    • If adverse effects occur, generally mild and will subside within 24 hours
  • Follow-up not usually required
Products
Detailed information on contraindications, cautions, adverse effects and interactions is available in individual drug monographs in the RxTx - CPS from CPhA, RxTx (Internet), Lexi-Comp, AHFS, www.drugs.com or other reliable drug monograph references. For comprehensive drug comparisons, see RxFiles charts (www.rxfiles.ca).
This information should be routinely consulted before prescribing.

Ingredient

Dosage

Levonorgestrel

1.5mg STAT

Ulipristal acetate

30mg stat

Yuzpe method

See treatment table

Prescribing and Billing Details
  • Currently DPEBB will pay an assessment fee of two times the dispensing fee for ulipristal acetate and levonorgestrel when prescribed by pharmacists with ECP certification.  See this algorithm for billing clarification.
  • No assessment fee will be paid when levonorgestrel is provided over-the-counter.
  • NIHB will not pay assessment fees for ECP products and does not allow the pharmacy to charge the fee to the patient.
  • Only products with an official indication from Health Canada for emergency contraception are considered for these guidelines.  Only the active ingredients in the "products" section are approved for pharmacist prescribing. 
Treatment Flowchart
Pharmacist Assessment Documents
References / Suggested Reading
  1. Graves G. Contraception. In RxTx - CTC online. Available at www.e-therapeutics.ca (by subscription). Available in Saskatchewan through SHIRP (www.shirp.ca).
  2. Whelan A.  Contraception. In RxTx - CTMA. Available at www.e-therapeutics.ca  (by subscription). Available in Saskatchewan through SHIRP (www.shirp.ca).
  3. Black A, Guilbert A. Canadian Contraception Consensus (Part 1 of 4). J Obstet Gynaecol Can 2015;37(10):S1–S28
  4. Wang L. A clinician’s guide to emergency contraception. In Medscape. Free access at http://www.medscape.com/viewarticle/831720_2.
  5. Ziemen M. Emergency contraception. In UpToDate online. Available at  www.uptodate.com (by subscription).
  6. Emergency Contraception.  In Dynamed online. Available at www.dynamed.com  (by subscription).
  7. Bullock H. Salcedo J. Emergency Contraception. Obstetrics and Gynecology Clinics 2015;42:699-712
  8. Jensen J. Emergency Contraception.Ob/Gyn Clinical Alert 2014;30:81-88. Available at  http://www.ctcfp.org/wp-content/uploads/OBGYN-Clinical-Alert-3-2014.pdf.     
Written by medSask
Posted Nov 2017