How effective is ellaOne® at preventing pregnancy?

How do I know if ellaOne® has worked?

You will know ellaOne® has worked when your next period starts. After taking ellaOne®, most women have a normal period at the expected time, but some may have their period later or earlier than normal.

Take a pregnancy test if:

  • your period is more than seven days late
  • your period is unusually light or unusually heavy
  • you experience symptoms such as abdominal pain, nausea, vomiting or breast pain
  • you have any doubt about being pregnant.

Pregnant after ellaOne®?

If you have accidentally taken ellaOne® during pregnancy, or have become pregnant despite having taken ellaOne®, HRA Pharma (the licence holder of ellaOne®) is interested in receiving more information about your pregnancy. Information is anonymous to preserve your confidentiality. You can report information at, or ask your doctor to do it for you. You are strongly advised to contact your healthcare professional as early as possible if you become pregnant.