Intrauterine Contraception
Intrauterine contraception is a form of contraception which is inserted into the womb.
There are two types of intrauterine contraception:
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Intrauterine system (IUS)
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Intrauterine device (IUD)
Intrauterine system (IUS)
How does it work?
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The IUS works by releasing the hormone progesterone.
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This thickens the mucus in the cervix so sperm cannot easily pass through and it thins the lining of the womb (endometrium) which makes it difficult for the egg to implant itself.
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How long does it last?
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It lasts for 3-5 years depending on the brand.
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Who can use it?
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Most women can use the IUS.
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However it may not be suitable if you have a history of*:
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Breast, cervical or endometrial cancer
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Blood clots
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Liver disease
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An untreated STI
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Pelvic inflammatory disease.
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How effective is it?
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The IUS is approximately 99% effective.
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Advantages
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There are many advantages to using the IUS such as:
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It is long-lasting and effective
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You do not have to remember to use it
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It can cause lighter periods
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It is an alternative to oestrogen contraceptives
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Disadvantages
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The disadvantages of the IUS include:
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Lack of prevention against STIs
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There are risks (e.g. pelvic infection, ovarian cysts and rarely damage to the womb when inserted)
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Side effects (e.g. headaches, acne, breast tenderness, mood changes)
Intrauterine device (IUD)
How does it work?
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An IUD is not a hormonal method of contraception.
It works by thickening the mucus in the cervix so sperm cannot easily pass through.
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How long does it last?
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It lasts for 5-10 years depending on the brand.
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How effective is it?
The IUD is approximately 99% effective.
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Who can use it?
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Most women can use an IUD.
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However it may not be suitable if*:
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You are pregnant
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You have unexplained vaginal bleeding (e.g. bleeding after sex or spotting)
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You have Untreated STI
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You have Pelvic inflammatory disease
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Advantages
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There are many advantages to using the IUD such as:
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It is long-lasting and effective
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You do not have to remember to use it
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Non-hormonal
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It works immediately
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It can be used as emergency contraception
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Disadvantages
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The disadvantages of the IUD include:
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Lack of prevention against STIs
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There are risks (e.g. pelvic infection and rarely damage to the womb when inserted)
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Side effects (e.g. change in periods)
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*This is not an extensive list. Please see your doctor for further advice.
Sources and Useful links
https://www.cdc.gov/reproductivehealth/contraception/index.htm
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https://www.plannedparenthood.org/learn/birth-control/iud
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https://www.nhs.uk/conditions/contraception/iud-coil/
https://www.nhs.uk/conditions/contraception/ius-intrauterine-system/
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https://sh24.org.uk/contraception/hormonal-coil
https://sh24.org.uk/contraception/non-hormonal-coil
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https://www.brook.org.uk/your-life/ius-intrauterine-system/
https://www.brook.org.uk/your-life/iud-intrauterine-device/
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