What is Etonogestrel?

Etonogestrel is a third-generation synthetic progesterone used in the hormonal etonogestrel implant called Nexplanon, which is inserted under the skin. It is also used in combination with oestrogen in the vaginal ring called Nuvaring.

Researchers have been exploring the use of etonogestrel as a form of male contraception^1, and a hormonal coil containing etonogestrel was trialled in 2015, but was unsuccessful².

How does Etonogestrel work?

Etonogestrel works in three ways: it prevents ovulation, changes your cervical fluid to stop sperm from entering your uterus, and changes the lining of your uterus so that a fertilised egg can’t implant³.

What is it in?

Implant

• Nexplanon

Vaginal ring

• Nuvaring

Is Etonogestrel androgenic?

Yes, but etonogestrel has very weak androgenic activity.. (Check out our ‘Androgens’ blog for more info on what this means).

Etonogestrel side effects

The side effects of etonogestrel are reported separately for the hormonal implant and the vaginal ring. To find out more about these visit the contraception pages on The Lowdown website.

Common side effects affecting people using the hormonal implant nexplanon include:^{1, 5}

• Changes to your periods, including irregular bleeding
• Headaches
• Breast tenderness
• Mood changes
• Acne
• Nausea
• Ovarian cysts
• Skin reactions
• Weight changes

Common side effects affecting 10% of people using the hormonal ring Nuvaring include⁶:

• Abdominal cramping 
• Nausea
• Yeast infections (thrush)
• Vaginal discharge 
• Genital itching 
• Headaches/migraines
• Low mood
• Low sex drive 
• Acne
• Weight gain
• Ring falling out

As of September 2024, 38% of Lowdown users indicated the implant had a negative effect on their mood, 45% experienced irregular bleeding and 50% lost their sex drive. For the vaginal ring, 55% of users said it had no impact on mood, 52% had lighter periods and 46% lost their sex drive. 

This data is self-reported from Lowdown contraceptive surveys.

Etonogestrel vs desogestrel

Etonogestrel is actually an active metabolite of desogestrel. This means your body converts desogestrel to etonogestrel in the body. They work in different ways to prevent pregnancy. Etonogestrel increases cervical mucus thickness, changes the lining of the uterus and prevents ovulation while desogestrel inhibits ovulation. Etonogestrel is used in the implant and ring while desogestrel is used in oral contraceptives. Etonogestrel is less androgenic than desogestrel.

Etonogestrel vs levonorgestrel

Etonogestrel and levonorgestrel are both used in implants. They both work by inhibiting ovulation. Etonogestrel is less androgenic than levonorgestrel. Levonorgestrel can also be used as a morning-after pill within 5 days of having unprotected sex.