Washington: After a 30-year-long study, scientist have finally provided convincing evidence that the combined oral contraceptive pill does, indeed, alleviate the symptoms of painful menstrual periods – dysmenorrhoea.

Although some previous studies and anecdotal evidence have suggested that the combined oral contraceptive pill could have an impact on painful periods, a 2009 review of all the available research by the prestigious Cochrane Collaboration concluded that there was limited evidence for pain improvement.

Now, Dr Ingela Lindh and her colleagues at the Institute of Clinical Sciences, Sahlgrenska Academy at Gothenburg University, Sweden, found that women who used the combined oral contraceptive pill suffered less severe pain compared with women who did not use it.

Young women often seem to suffer more from painful periods than older women, and the researchers also found that increasing age did alleviate the symptoms, but the effects of pill use and age were independent of each other, with the pill having a greater effect.

The researchers questioned three groups of women who reached the age of 19 in 1981, 1991 and 2001. Each group included approximately 400 to 520 women, who provided information on their height, weight, reproductive history, pattern of menstruation and menstrual pain, and contraceptive use.

Five years later they were assessed again at the age of 24.

“By comparing women at different ages, it was possible to demonstrate the influence of COCs on the occurrence and severity of dysmenorrhoea, at the same time taking into account possible changes due to increasing age. We found there was a significant difference in the severity of dysmenorrhoea depending on whether or not the women used combined oral contraceptives,” said Dr Lindh, who is also a registered nurse and midwife.

“We found that combined oral contraceptive use reduced dysmenorrhoea by 0.3 units, which means that every third woman went one step down on the VMS scale, for instance from severe pain to moderate pain, and which meant that they suffered less pain, improved their working ability and there was a decrease in the need for analgesics. On the VAS scale there was a reduction in pain of nine millimetres,” she noted.

Independent of the effect of COC use, the researchers found that increasing age reduced the severity of dysmenorrhoea but not as much as COC did; it shifted women down 0.1 units on the VMS scale and five millimetres on the VAS scale.

The finding has been published online in Europe’s leading reproductive medicine journal Human Reproduction.

ANI