Painful breasts (Mastodynia or Mastalgia) is the most common breast symptom experienced by women [1], and may affect up to 70 % of women in their lifetime [2]. It may be severe enough to interfere with usual daily activities, and its effect on quality of life often is underestimated. 1 It is not unusual for women to have 2–3 days of mild breast pain premenstrually, but 8–30 % of women report moderate to severe breast pain with a duration of 5 or more days each month [3].

The etiology of mastodynia is not well understood. The relationship to the menstrual cycle suggests a hormonal cause. It is postulated by many that a hormone imbalance is responsible: either elevated estrogen levels or low progesterone levels, or an abnormal estrogen/progesterone ratio [4].

1. Smith et al, Evaluation and Management of Breast Pain. Mayo Cin. Proc. 2004;79:353-372
2. Ader et al, Cyclical mastalgia: prevalence and associated health and behavioral factors. J Psychosom Obstet Gynaecol 2001;22:71–6.
3. Society of Obstetricians and Gynecologists of Canada (SOGC), Mastalgia. J Obstet Gynaecol Can. 2006 Jan;28(1):49-71
4. Wang et al, Epidemiology and Endocrinology of Benign Breast Disease. Breast Cancer Res Treat 1985; 6: 5-36