This is an updated guideline from the FSRH. There isn't really anything very new in this, so I've just summarised some of the things I wasn't aware of or was a bit hazy on.
Method of action
Copper intrauterine devices (Cu-IUD) provide a hostile environment to fertilisation, have a cervical mucous effect and an anti-implantation effect.
Levonorgestrel Intrauterine Systems (LNG-IUS) like Mirena and Jaydess (and now Levosert) have an uncertain method of action. They seem to work through cervical mucous and by effects on the endometrium. Some women stop ovulating with an LNG-IUS.
Follow up after insertion
This isn't mandatory, though women should be advised of the signs and symptoms of infection, perforation and expulsion.
How long can a coil be used?
Cu-IUD with 300 or more mm2 of copper. If inserted aged 40 or over they can be continued until 1 year after the menopause if over 50, or 2 years after the menopause if under 50.
LNG-IUS. If it is inserted aged 45 or over, Mirena can be used for 7 years, or if the woman is amenorrhoeic, until the menopause.
Benefits of coil use
Endometrial and cervical CA. Cu-IUD may be associated with a reduced risk of endometrial and cervical CA.
Dysmenorrhoea. Mirena may reduce primary dysmenorrhoea and pain from endometriosis and actinomyosis.
Ensure that there is no infection, pregnancy or other gynaecological problem.
Cu-IUD. NSAIDs can be used. If these are ineffective, tranexamic acid can be tried.
LNG-IUS. There is no evidence that mefenamic or tranexamic acid help. The FSRH advises a 3m course of the COC (though there is no evidence behind this).
Thrush. There is no consistent evidence of a link between Cu-IUD and thrush.
Bacterial Vaginosis (BV). There is a link between the Cu-IUD and BV. People with recurrent infections may wish to consider removal. It is uncertain as to whether there us a link between the LNG-IUS and BV.
Actinomyces like organisms (ALOs). These are commensal organisms and only rarely causes symptoms. There is no need to remove a coil in asymptomatic patients. Coils can be removed and inserted with ALOs present. If the patient has symptoms, consider other causes first, then consider removal of the coil.
PID. Removal is not required, though should be considered if there is no improvement after 3d. The benefits of removal must be weighed against the risk of pregnancy.