The study found an increased risk of cancer, contradicting some earlier evidence that suggests the opposite.
Taking a hormonal contraceptive for at least 5 years is associated with a possible increase in a young woman's risk of developing a rare tumour, glioma of the brain. This project focussed on women aged 15-49 years and the findings are published in the British Journal of Clinical Pharmacology.
Hormonal contraceptives, including oral contraceptives, contain female sex hormones and are widely used by women all over the world. While only a little is known about the causes of glioma and other brain tumours, there is some evidence that female sex hormones may increase the risk of some cancer types, although there is also evidence that contraceptive use may reduce the risk in certain age groups. "This prompted us to evaluate whether using hormonal contraceptives might influence the risk of gliomas in women of the age range who use them," says research team leader David Gaist, MD, of the Odense University Hospital and University of Southern Denmark.