Contents
Introduction
Intrauterine devices (IUD) are a commonly prescribed form of contraception. They are a LARC – long-active reversible contraception, and as such are often recommended ahead of other forms of shorter acting contraception.
IUDs are a small T-shaped pieces of plastic, coated with wither copper or a progesterone releasing compound, which is inserted through the cervix, trans-vaginally, into the uterus. This is a relatively straight-forward procedure, not dissimilar to a smear test, and can be performed in the GP clinic rooms.
There are two main types of IUD:
- Hormonal IUD (Mirena)
- Copper IUD
Terminology
The terminology can be a bit confusing and is not always standardised. IUD (Intrauterine device) can refer to both the mirena IUD or the copper IUD. Generally these days most people have a mirena IUD, and the copper IUD now seems to be quite rare (certainly in my experience).
Some people use “IUD” to generally mean Mirena, and typically specify “copper” when this appropriate.
You might also see some other terms. As far as I can tell IUC (intrauterine contraception) and IUCD (intrauterine contraceptive device) can also refer to either the copper or the mirena variant.
I have also seen IUS (intrauterine system) used to refer to the mirena variant only (and not the copper coil).
Some people also sometimes refer to these devices as “coils” As far as I can tell, this harks back to the time when only the copper variant was available, and refers to the “coil” of copper that is wound around the plastic device.
Hormonal IUD
- Contraceptive
- Treatment for menorrhagia
- Symptoms usually subside within 3-6 months of insertion
- Many women will have lighter periods, and some will have none at all
- Prevention of endometrial hyperplasia during oestrogen replacement therapy
- It is recommended for use as a contraceptive device in women with heavy periods.
- The reduction in menorrhagia may take 3-6 months to occur
Efficacy
- Quoted as >99% effective
- Described as: if taken correctly, then during the course of 5 years, <1% of women using the IUS will become pregnant
Mechanism
- Prevents proliferation of the endometrium (making implantation difficult)
- Thicken cervical mucus (creating a ‘plug) that sperm cannot penetrate
- Suppresses ovulation (in some women, some of the time)
- Long-term fertility is not altered
- Lasts for 5 years
- Can stay in for longer in the over 45’s
- Reduced risk of PID
- Reduced risk of dysmenorrhoea
- Reduced blood loss
- Reduced risk of ectopic pregnancy (compared with copper IUD)
- Risk of ectopic pregnancy if pregnancy is present is still greater than general population
- Very few systemic effects
- E.g.. drug interactions are negligible, and thus this is a suitable method for a woman taking a drug that interacts with progesterone.
Risks and Contraindications
- Slight increased risk of ectopic pregnancy – although overall chance of pregnancy is very low!
- Should be avoided for 5 years after breast cancer, due to effect of progesterone
- However, systemic effects of progesterone are very small due to location of device.
- Infection during first 20 days after administration (rare). Signs might include:
- Pelvic / lower abdo pain
- Discharge
- Irregular bleeding
- Expulsion and displacement – the IUD can be moved by uterine contractions
- Perforation (very rare) – usually occurs at the time of insertion.
Side effects
- Changes in the pattern and duration of menstrual bleeding
- E.g. spotting or prolonged bleeding
- Mastalgia (breast pain)
- Mood changes
- Side effects reduce over time, and after several months may be negligible. Many women may have no bleeding at all – other may have light regular bleeding, and a small minority maintain an erratic pattern, but bleeding is still likely to be light.
- Functional ovarian cysts – these are usually asymptomatic, and resolve spontaneously, but ultrasound monitoring is recommended
Prescribing
If there is risk / signs of infection, this should be treated.
- Speculum examination is usually required to check for any structural abnormalities or infection that may prevent or contra-indicate insertion of the IUD
Can be done in clinic or at the GP. Usually takes 15-20 minutes. Will be uncomfortable, some women may find it painful, and a local anaesthetic can be used. There may be light bleeding and some discomfort for the first few days
If there is any risk of pregnancy, a pregnancy test should be performed first.
If fitted in the first 5 days of the cycle, then is effective immediately
If fitted at another time in the cycle, condoms or another contraception need to be used for 7 days
The IUD is usually checked 3-6 weeks after insertion to ensure it is properly in place.
- After Pregnancy – Can be fitted 4 weeks after birth. Another method of contraception will be needed from day 21 until the IUD is fitted
- After abortion or miscarriage – Can be fitted immediately, and will be immediately effective.
Advising the patient
- Show them how the IUD sits in the uterus
- Advise that there are two strings that poke down into the vagina. The patient can feel these strings in the vagina to know the IUD is present
- Rarely these may cause irritation (usually to the man) during sex, in which case, they can be cut shorter (but not too short – as you need them to get the IUD out!)
- Advise the patient that:
- A normally fitted IUD cannot be felt
- If the women has any pelvic pain, or it feels like she is ‘sat on a match stick’ the IUD may have slipped out (rare). She can check for herself by feeling for the strings, and she might feel part of the IUD itself. She should make an appointment with the GP
- Tampons can be used without issue
Removal of the IUS
- Can be removed at any time
- Fertility returns quickly
- Sperm can live for up to 7 days. If you are planning on removing the IUD, and do not want to become pregnant, additional contraception should be used in the 7 days before IUD removal.
Copper IUD
Contains only plastic and a copper coil
Two types:
- Lasts 5 years
- Lasts 10 years
Efficacy
- Quoted as >99% effective
- Described as: if taken correctly, then during the course of 1 year, <1% of women with an IUD will become pregnant
Mechanism
Risks and Contraindications
Slight increased risk of ectopic pregnancy – although overall chance of pregnancy is very low!
Infection during first 20 days after administration (rare). Signs might include:
- Pelvic / lower abdo pain
- Discharge
- Irregular bleeding
- If symptoms of infection are present during this time, the woman should attend as a matter of emergency.
Expulsion and displacement – the IUD can be moved by uterine contractions
Perforation (very rare) – usually occurs at the time of insertion.
Previous history of PID
All women under 25
Women under 25 AND:
- New partner
- More than one partner in the last year
- Their partner regularly has other partners
Side effects
Tranexamic acid – 1g/6-8h for up to 4 days – an antifibrinolytic, can reduce menorrhagia by 50%
Mefanamic acid – 500mg/8h – an NSAID – antiprostaglandin – taken during periods of heavy bleeding, can reduce menorrhagia by 30%. Is also useful for dysmenorrhoea.
- Contraindicated in peptic ulcer disease
Prescribing
Can be done in clinic or at the GP. Usually takes 15-20 minutes. Will be uncomfortable, some women may find it painful, and a local anaesthetic can be used. There may be light bleeding and some discomfort for the first few days
- Women may be advised that 30mg of ibuprofen (NSAID) before the procedure can alleviate pain
Can be fitted at any time in the cycle, and is effective immediately
If there is any risk of pregnancy, a pregnancy test should be performed first.
If there is risk / signs of infection, this should be treated.
The IUD is usually checked 3-6 weeks after insertion to ensure it is properly in place.
Advising the patient
Show them how the IUD sits in the uterus
Advise that there are two strings that poke down into the vagina. The patient can feel these strings in the vagina to know the IUD is present
Rarely these may cause irritation (usually to the man) during sex, in which case, they can be cut shorter (but not too short – as you need them to get the IUD out!)
Advise the patient that:
- A normally fitted IUD cannot be felt
- If the woman has any pelvic pain, or it feels like she is ‘sat on a match stick’ the IUD may have slipped out (rare). She can check for herself by feeling for the strings, and she might feel part of the IUD itself. She should make an appointment with the GP
Tampons can be used without issue.
Removal of the IUD
- Can be removed at any time
- Fertility returns quickly
- Sperm can live for up to 7 days. If you are planning on removing the IUD, and do not want to become pregnant, additional contraception should be used in the 7 days before IUD removal.