Altered bleeding patterns

Altered bleeding patterns can occur with both levonorgestrel-releasing intrauterine contraceptive devices (LNG-IUDs) and copper IUDs, but are more common with LNG-IUDs.

With copper IUDs, bleeding is usually heavier and of longer duration than before insertion, but cycle length does not change. Breakthrough bleeding may occur in the first few months of use.

With LNG-IUDs, unscheduled light bleeding is common during the first 3 to 6 months, after which the usual pattern is amenorrhoea, or light regular bleeding or spotting.

Exclude other causes of bleeding, such as pregnancy, sexually transmitted infections (eg chlamydia), and vaginal, cervical or uterine pathology. If no other cause of bleeding is suspected, provide reassurance that bleeding can be expected and is not harmful.

Evidence for medical management of frequent or prolonged bleeding is limited; options include adding:

• a combined hormonal contraceptive taken continuously or cyclically for up to 3 months (or longer on a case-by-case basis, although this has not been studied and data on effectiveness and risks are lacking)
• a 5-day course of a nonsteroidal anti-inflammatory drug (NSAID) or (if bleeding is heavy) tranexamic acid; see Heavy menstrual bleeding for dosages.

Other options (with low-level, anecdotal or conflicting evidence) include adding oral norethisterone (see Heavy menstrual bleeding for dosage), or adding a levonorgestrel progestogen-only pill (twice daily for 20 days). Alternatively, replace or remove the IUD.