Contraceptive-induced amenorrhoea leads to reduced migraine frequency in women with menstrual migraine without aura

BACKGROUND: Menstrual migraine without aura (MM) affects approximately 20% of female migraineurs in the general population. The aim of the present study was to investigate the influence of contraception on the attacks of migraine without aura (MO) in women with MM. FINDINGS: 141 women from the general population with a history of MM according to the International Classification of Headache Disorders II (ICHD II) were interviewed by a headache specialist. Of 49 women with a history of MM currently using hormonal contraception, 23 reported amenorrhoea. Significantly more women with amenorrhoea reported no MO- days during the preceding month compared to women without amenorrhoea (OR 16.1; 95% confidence interval (CI) 1.8-140.4; P = 0.003). A reduction of MO-frequency was more often reported in women with than without amenorrhoea (OR 3.5; 95% CI 1.1-11.4; P = 0.04). CONCLUSION: Amenorrhoea leads to a reduction of MO-frequency in women with MM using hormonal contraceptives. Future prospective studies on MM should focus on contraceptive methods that achieve amenorrhoea.