How effective is an intrauterine device (typical use)?
99% (both types)
What is it?
The IUD is a small, T-shaped plastic device that is inserted and left inside the uterus. There are two types available in the United States: the hormonal IUD and the copper IUD.
How does it work?
The hormonal IUD releases a small amount of progestin into the uterus. Progestin thickens the cervical mucus, thins the endometrium, and may make sperm less mobile. The copper IUD releases a small amount of copper into the uterus. It causes a reaction inside the uterus and fallopian tubes that works like a spermacide.
Advantages
- You do not need to remember it every day.
- The hormonal IUD works for 5 years.
- The copper IUD works for as long as 10 years.
- It does not interrupt sex.
- The hormonal IUD will make periods lighter.
- If you wish to become pregnant, simply have the IUD removed.
Disadvantages
- It must be inserted and removed in a doctor’s office or clinic.
- It does not protect against sexually transmitted diseases.
Side Effects
Hormonal IUD (Mirena®):
- Irregular periods
- Vaginal discharge
- Headache
- Nausea
- Breast tenderness
- Depression
- Amenorrhea (lack of periods)
Copper IUD (ParaGard®):
- Heavy periods
- Irregular periods
- Painful periods
- Vaginal discharge
These serious problems may happen during, or soon after, insertion:
- Expulsion
- Perforation
- Infection