Ethinylestradiol with etonogestrel

How it works

The ring releases both hormones for transmucosal absorption, suppressing ovulation while thickening cervical mucus and altering the endometrium; the vaginal route avoids first-pass hepatic metabolism.

Prescribing in practice

• Despite the non-oral route the systemic VTE and arterial risks are the same as for combined oral contraceptives, so apply the full UKMEC contraindication screen.
• Counsel on what to do if the ring is expelled or left out beyond the permitted window, as efficacy may be compromised.
• Efficacy can still be reduced by enzyme-inducing drugs.

Monitoring

Check blood pressure and reassess cardiovascular and VTE risk at initiation and periodic review.

Counselling the patient

• Know how long the ring can be out before back-up contraception is needed.
• The ring does not protect against sexually transmitted infections.
• Seek urgent help for leg swelling, chest pain, breathlessness or sudden severe headache.

Evidence & guidelines

UKMEC applies the same combined-method eligibility criteria to the contraceptive vaginal ring as to oral preparations.