With informed consent, the long-acting methods can also be used successfully by women who have problems with compliance using other methods e.g. women with psychotic disorders, intellectual disability or who are intravenous drug users. Previously, the use of DMPA in the intellectually disabled, without informed consent, has been severely criticised. Contraindications Progestogen-only methods are contraindicated in suspected pregnancy, breast cancer and undiagnosed vaginal bleeding. Giving DMPA to a woman with a severe bleeding disorder may result in a large haematoma at the injection site. Progestogen-only methods are unsuitable for women unwilling to accept menstrual changes.
Relative contraindications are active viral hepatitis and severe chronic liver disease.
For all progestogen-only methods, with the possible exception of DMPA, drug interactions are likely with many anticonvulsants, rifampicin, spironolactone and griseofulvin. This may result in lowered efficacy. The most common adverse effect of progestogen-only methods is disturbance of bleeding patterns. Erratic cycle length, prolonged episodes of bleeding, and nuisance spotting, but not heavy bleeding, are common. There are more problems with injectables and implants than with the mini-pill.