This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Emergency contraception (EC) and obesity

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Emergency contraception (EC)

  • available evidence suggests that effectiveness of the copper intrauterine device (Cu-IUD) is not affected by body weight or BMI
  • 1.5 mg levonorgestrel emergency contraception (LNG-EC) appears to be less effective in women with BMI >26 kg/m2 or weight >70 kg
  • Ulipristal acetate EC (UPA-EC) may be less effective in women with BMI >30 kg/m2 or weight >85 kg

FSRH state (1):

  • women should be informed that the Cu-IUD is the most effective method of EC

  • women should be informed that BMI >26 kg/m2 or weight >70 kg may reduce the effectiveness of oral EC, particularly of LNG-EC

  • consider UPA-EC and, if this is not suitable, double-dose (3 mg) LNG-EC if BMI >26 kg/m2 or weight >70 kg. The effectiveness of double-dose LNG-EC is unknown

  • double-dose UPA-EC is not recommended for women of any body weight or BMI


  • FSRH (April 2019). Overweight, Obesity & Contraception

Related pages

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page