How the ring works

The vaginal ring is a small, flexible 5cm diameter plastic ring that you insert into your vagina. It releases copies of 2 natural hormones – oestrogen and progesterone – to stop pregnancy.

The ring releases these hormones at a steady rate, getting them into your bloodstream through your vagina and changing the hormone levels in your body.  

While it can affect many of your body’s organs, the effects that make it an excellent contraceptive are:

  • it stops you from producing an egg, which is known as ovulation – no egg means there’s nothing to fertilise

  • it thickens the cervical mucus, this stops sperm from travelling from the vagina into the uterus

  • it thins the lining of the uterus, a fertilised egg can’t implant in a uterus with a thin lining (this is a backup measure as most people won’t produce an egg at all)

How the ring affects the body

The ring’s hormones travel all over the body in the bloodstream.

  • it stops the pituitary gland in the brain from releasing the hormones that trigger ovulation each month, so no egg is released, and therefore there’s nothing to fertilise

  • thickens cervical mucus so sperm can’t get through

  • thins the lining of the uterus so an egg can’t implant

  • helps reduce acne

  • can increase breast tenderness

  • slightly increases the risk of breast cancer

  • reduces the risk of cancer of the lining of the uterus

How the ring affects your ovaries and uterus 

During ovulation, the cervical mucus is slippery. This makes it easier for sperm to enter the uterus. The lining of the uterus is thicker, so it’s easier for an egg to implant.

The hormones in the ring change both the uterus and ovaries. No egg is released, the mucus is thicker, and the lining of the uterus is thinner.

Types of ring

In the UK there are, for now, 2 brands of vaginal ring available. They're called NuvaRing and SyreniRing.

NuvaRing: a flexible, transparent ring with a 5.4cm diameter.

Contains: 11.7 mg etonogestrel (a progestogen) and 2.7 mg ethinylestradiol (a synthetic oestrogen).

Release rate: an average of 0.120 mg and 0.015 mg respectively every 24 hours, over 3 weeks.

SyreniRing is a newer ring which is almost identical, with the same ingredients, but with a longer shelf life so you may be able to get up to a year’s supply at once.

Everything you wanted to know about sexual health and wellbeing - your questions answered by our expert team.