• progestogenic effect on endometrium

  • prevents implantation

• within 1 month

  • high intrauterine concentrations induce endometrial atrophy

• little effect on HPO axis

• majority of women continue to ovulate

• failure rate \<1%

• licensed for 5 years contraceptive use

• licensed for 4 years to provide endometrial protection

• if inserted >45yo then can have up to menopause

• can be inserted any time in menstrual cycle if not pregnant and no risk of conceptoin

  • condoms or abstinence advised for 7d after unless in first 7 days

-

risks

• perforation

  • 0.9/1000 insetions

• expulsion

  • 1/20

  • most common 1st month

• ectopic pregnancy

  • no increase risk of ectopic pregnancy with current Cu-IUD

  • 0.02/100 woman years

  • 0.3/100

• return to fertility

  • doesn’t cause delay in return to fertility

  • mean time to pregnancy = 3/12

• Pelvic infection

  • most strongly related to insertion procedure adn to background risk of STI

  • 1.6/1000 women years

• bleeding

  • systemic absorption of LNG occurs

  • irregular bleeding/spotting first 6/12

  • by 1 year amenorrhoea or light bleeding = usual

• cyst may occur

  • not clinically problme

• menorrhagia/endometrial protection