In the UK, the only injectable currently licensed for long-term use is depot medroxyprogesterone acetate (DMPA) – Depo-Provera – and it has been given additional approval as a first-line contraceptive. It has been repeatedly endorsed by the expert committees of prestigious bodies, such as the International Planned Parenthood Federation and WHO. DMPA is even safer than COCs, in spite of the adverse publicity it often receives. Anxiety about this method was generated by animal research of very doubtful relevance to humans. WHO data indicate that DMPAusers have a reduced risk of cancer, with no overall increased risk of cancers. | Injectables Background In the UK the only injectable currently licensed for long-term use is depot medroxyprogesterone acetate DMPA - Depo-Provera - and it has been given additional approval as a first-line contraceptive. It has been repeatedly endorsed by the expert committees of prestigious bodies such as the International Planned Parenthood Federation and WHO. DMPA is even safer than COCs in spite of the adverse publicity it often receives. Anxiety about this method was generated by animal research of very doubtful relevance to humans. WHO data indicate that DMPA-users have a reduced risk of cancer with no overall increased risk of cancers of the breast ovary or cervix - and a fivefold reduction in the risk of carcinoma of the endometrium relative risk . There is still the possibility of a weak cofactor effect on breast cancer in young women similar to that with COCs. However this is unproven and the apparent association may be due to surveillance bias in early years of use by the younger women. Administration There are actually two injectable agents available DMPA 150 mg every 12 weeks and Noristerat norethisterone enanthate Schering Health Care 200 mg every 8 weeks both given by deep intramuscular injection in the first 5 days of the menstrual cycle. Injections may also be given beyond day 5 with 7 days added precautions if it is near certain that a conception risk has not been taken. The injection sites in the UK 80 usually in the right upper quadrant of either buttock should not be massaged. Noristerat is not licensed for long-term contraception though it can be so used off-licence p. 150 and will not be considered further here. Subcutaneous DMPA There is interest in this different route of administration under the skin of the abdominal wall or upper thigh. The US-marketed product is termed depo-subQ provera 104. Not yet available in the UK it delivers a lower dose of medroxyprogesterone acetate 104 mg than standard Depo-Provera for a similar duration of
