Q:After surgery and radiotherapy for cancer (uterus) I am taking three tablets of Provera (100 mg) daily. I am worried about the "long term effects" of this drug. A.F., Gillingham.....
and alsoAt the age of 18 I took the morning after pill, knowing virtually nothing about it. I am now 21 and would like to know everything about it, including all the side effects. J.M., Nuneaton.....
A:Depot medroxy-progesterone, more commonly known as depo provera or "the morning after" pill, is a fantastic example of medical self justification and Mad Hatter type logic. This injectable contraceptive is a synthetic version of the female hormone progesterone. It works by stopping ovulation and suppressing the production of oestrogen.
Doctors prescribe it to treat irregular periods, failure to menstruate, endometriosis or uterine bleeding. Sometimes it is used to treat breast or uterine cancer or painful periods. But it is perhaps best known as "after the fact" contraception. Women who have had unprotected sex often go to their doctor in a panic and then are given a powerful dose of the stuff, which will call a halt to ovulation in progress.
In an earlier WDDTY we wrote extensively about some of the side effects of depo provera, particularly its tendency to cause corneal changes in the eye (see Vol 1 No 3). As its manufacturer Upjohn admits, one of the problems is also its potential (fivefold increase) to cause birth defects. In other words, if you take the morning after pill and it doesn'twork and you get pregnant, you are five times as likely to give birth to a child with heart or limb reduction defects.
Perhaps most puzzling, this drug is used to treat uterine or breast cancer, when it has been shown to cause breast cancer in beagles!
Nevertheless, the drug was recently in the medical news after the World Health Organization completed a study in five participating hospitals of some 12, 000 women. The study concluded that there was only a slightly elevated risk of breast cancer due to DMPA use, mainly within the first four years of initial exposure, in women under 35. The risk did not increase with duration of use.
These results, published in the 5 October 1991 Lancet encouraged the editors to enthuse about the great potential of this drug, particularly in the Third World. Because it it tends to increase haemoglobin concentrations, it could help prevent anaemia. They trotted out statistics about the dangers of death in childbirth. "Contraceptives save lives of both mothers and their children," they wrote piously. (Of children?) Health care workers, they concluded, therefore have no less than a "moral responsibility" to provide reliable contraceptives like DMPA.
What no one seems to include in the equation are any other possible risks. The British Medical Journal (6 July 1991) published a study showing that women who had used DMPA for five years had significantly lower bone density (7.5 per cent) than those who hadn't, which means that use of the drug could be a risk factor for osteoporosis in later life.
This may also be something to consider if your doctor prescribes "opposed" HRT ie, the kind with progestogens to prevent osteoporosis. The cure may ultimately bring on the disease.
Against these and other potential risks you must calculate the questionable benefits of this drug in its various uses. Family Health International of North Carolina did a calculation of life expectancy gains or losses of patients using DMPA versus those who didn't. They concluded that when all risks of cancer and potential benefits are worked out, if you are on this drug for five entire years, you may live at most 18 days longer than you would if you didn't.