Depo Provera (medroxyprogesterone acetate, DMPA) when given as 150 mg by deep intramuscular injection every 12 calendar weeks (84 days+5 days), is a highly effective contraceptive with a very low failure rate comparable to modern copper IUDs and lower than many other methods. It should be available as a first line method to all who wish to make an informed choice about reversible methods of contraception. Pre-use counselling is essential to minimise the effect of menstrual change which occurs in most patients. However there is great patient variability. Use of DMPA is independent of intercourse and also independent of the user's memory (and thus of continuing motivation), other than remembering the 12 weekly appointments. For many women this is a great advantage. Oral contraceptive methods involve remembering to take a pill each day, in the case of the progestogen only pill within the same three hours each day. This places considerable strain on women who lead irregular lifestyles, who are very busy or travel frequently. Such women often describe a constant 'fear of forgetting', especially with the POP. The main potential disadvantage of DMPA in this country are likely to be menstrual disturbance and weight gain. The combined oral contraceptive pill gives the appearance of excellent cycle control because it removes the natural cycle altogether and replaces it with an artificial one. All progestogen-only methods, whether low or high dose, lead to menstrual disturbances, so in this respect DMPA is not unique. Although troublesome, the menstrual disturbances which occur in DMPA users very rarely require operative medical intervention, and can often be improved simply by short courses of oestrogen or shorter injection intervals. Again, women need to know what can be done so that they are aware that they should seek advice early, rather than miserably waiting.for their 12 week appointment. DMPA has no appreciable effects on blood pressure or thrombosis risk. In this it has an advantage over the combined oral contraceptive pill, and provides a simple, effective alternative for women who cannot use the pill for these reasons. Similarly, it has been suggested that women who suffer from focal migraine and are therefore advised against use of the combined oral contraceptive pill can still use progestogen-only contraceptives. Although the POP is medically safe in these circumstances, in young women it is less effective, and involves strict time keeping, which will be disadvantageous for some women. Side effects, long term use and schedules of administration are also discussed. The use of local protocols to allow nurse administration is to be supported both in general practice and the clinic situation. Perhaps the most important issue surrounding the use of DMPA is that of patient information. The method has had a particularly bad public image, which naturally makes potential users anxious and subject to misinformation from poorly informed or biased sources. Also, it is temporarily irreversible during its three months duration, so the duration of any problems or anxieties resulting from side effects may be longer than for other methods. It is of paramount importance that easily understood, accurate patient information leaflets are available, since biased and inaccurate information is readily available from women's magazines, perpetuating the myths surrounding the method.
PIP: This study presents a review of current clinical evidence on the usefulness of Depo Provera (medroxyprogesterone acetate, DMPA), a long-term method of reversible contraception. It is taken as an intramuscular long-acting agent (150 mg every 12 calendar weeks). The user failure rate approaches the method failure rate, which varies considerably with age. In terms of metabolic effects, it did not show changes in cholesterol or triglycerides and had no significant effect on hemostasis, which impairs the oral glucose tolerance test (OGTT) glucose response and increases insulin response. There were no significant adverse effects on long term growth and development in DMPA exposed children and no delays in return to fertility. For cancers, controlled surveillance of DMPA users found no overall increased risk of ovarian, liver or cervical cancer and even found a prolonged protective effect in reducing the risk of endometrial cancer. However, increased risk of breast cancer in recent users was observed; this could be due to enhanced detection of breast tumors of women using DMPA. The main DMPA disadvantages are menstrual disturbance and weight gain after 1 year. Bone mineral density (BMD) is found to be significantly lower. DMPA patients' sociodemographic characteristics and behavior placed then at higher risk for adverse pregnancy outcome in low infant birth weight and also possibly in polysyndactyl and chromosomal defects. Thus, for injectable progestogen, the data is again less conclusive. Risks may be similar to POP (progestogen-only contraceptive pill), but did not reach significance in the meta-analysis.