For every time, there is a season and, for every woman - if drug companies have their say - there is a contraceptive pill. Despite the mountain of evidence that the Pill can be dangerous, even life-threatening, the pharmaceutical industry keeps tinkering here and there for a new breakthrough drug.

The latest one from the US mostly promises to relieve women from that ‘curse’ of womanhood: the monthly menstrual period. With Seasonale, a Pill developed at the Eastern Virginia Medical School and now produced by Barr Laboratories, users only need to suffer one period a season.

Ordinary contraceptive pills are taken on a three-weeks-on, one-week-off cycle. The week off permits withdrawal bleeding, which mimicks a normal period. (In fact, it is bleeding due to the withdrawal of hormones in the Pill that keep the body in a state where the womb doesn’t need to plump up for implantation.)

Seasonale, on the other hand, must be taken for 84 days consecutively, with only one week off before the next 84-day cycle, cutting a woman’s period count by two-thirds.

Doctors such as John Guillebaud, Professor Emeritus of family planning and reproductive health at University College London, and a trustee of the Margaret Pyke Memorial Trust, has gone on record to say that limiting periods is not a bad idea. Women now begin the menarche earlier than their predecessors, have fewer babies and breastfeed for shorter periods, if at all. Consequently, he says, they have too many periods, leading to diseases such as endometriosis, and ovarian and endometrial cancer. A period-suppressing pill, he suggests, gives the modern woman the hormonal rests her forebears enjoyed naturally.

“While some people may worry that it’s not ‘natural’ to suppress menstruation,” he says, “it’s actually more natural than having so many periods.”

Seasonale is also being sold as the solution for bad periods - cramps, migraines, or heavy or painful periods - as well as a means of preventing teenage pregnancy.

Like ordinary Pills, Seasonale contains oestrogen (30 mcg of ethinyloestradiol, a synthetic) and progestin (150 mcg of levonorgestrel, a synthetic progesterone), and is as safe as other Pills (Contraception, 2003; 68: 89-96). Minor side-effects include nausea, vomiting, bleeding weight gain, breast tenderness and difficulty wearing contact lenses. The more worrisome effects include bloodclots, stroke, blocked blood vessels, gallbladder disease, liver tumours, high blood pressure, problems with fat metabolism, and cancers of the breast and reproductive organs.

And despite the promise of no periods, women taking Seasonale routinely have ‘breakthrough’ bleeding. In cigarette-smokers, it raises the risk of serious cardiovascular effects. It should also never be taken with St John’s wort, which will counteract its contraceptive effect.

What nobody really knows is whether the dangers multiply as a result of taking the hormones for longer periods of time without a break. As with most new drugs, long-term studies were not carried out before approval was granted, so the millions of young women who opt to take this drug will be its first human guinea pigs.

Seasonale proponents like Guillebaud brush this potential danger aside, arguing that women have long ‘tricycled’ the Pill to suppress periods for holidays or special evenings, and many doctors have been prescribing contraceptives without much of a break for many years. In a sense, Seasonale is merely legitimising what have been unofficial prescribing habits. But until long-term studies are done, the true effects won’t be known.

Lynne McTaggart