Menstrual cramps, when due to primary dysmenorrhea, are caused by the action of endometrial prostaglandins and is a normal process of menstruation, to a degree, that then causes the contractions of the uterus. However, for some women, it is more than mild discomfort and can be mild, moderate or severe and depending on the pain level, needs to be treated during those painful days, as well as a strategy to try to reduce the pain for the next menstrual cycles. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most common acute treatment, but can cause peptic ulcers, liver or kidney disorders and allergic reactions. Hormonal contraceptives are also commonly used to manage the chronic nature of the problem. Herbal and nutritional therapies have been shown to reduce acute pain in several published studies and have included valerian, ginger, cinnamon and niacin. High dose Vitamin D before the menstrual cycle and regular select doses of fish oils have been shown to reduce the subsequent painful cycles.
Previous studies have shown that metabolism and absorption of vitamins and minerals may play a role in the etiology of and treatment of menstrual disorders. Lower serum calcium levels have been associated with muscle spasm and contraction. Vitamin D may help to regulate prostaglandins.
The current randomized placebo-controlled trial attempted to determine the effect of combined Calcium-Vitamin D and Calcium alone on the intensity of menstrual pain and menstrual blood loss in women with primary dysmenorrhea. Iranian women aged 18-32 with painful and regular menses in the previous 6 cycles were given either Calcium-Vitamin D tablets of 1,000 mg Calcium carbonate and 5,000 units of Vitamin D, or Calcium carbonate alone 1,000 mg or placebo. Each group took their tablet once daily from day 15 until the end of the menstrual flow, for one cycle.
Compared to placebo, the mean pain intensity was lower in both the Calcium-Vitamin D group (-0.7) and the calcium alone group (-1.6) but was only statistically significant in the calcium alone group. Menstrual blood loss was not significantly different in any of the 3 groups. The mean percent change of pain intensity from baseline was 20% in the Calcium-Vitamin D group, 32% in the calcium alone group and 6% in the placebo group.
Commentary: This study confirms the effectiveness of something as simple as Calcium 1,000 mg/day starting on day 15 and through the menstrual flow in reducing the severity of primary dysmenorrhea. In an earlier trial, the authors demonstrated that effectiveness of 600 mg/day from day 15 through menses in reducing menstrual pain intensity. Other research has shown that dysmenorrhea was significantly less common in young women who consumed 3 or 4 servings of dairy products every day compared to those who consumed no dairy. Another study showed that women with very severe dysmenorrhea reported lower intake of dairy products. On the other hand, there was a study that reported a positive relationship between consumption of dairy and severity of pain. Despite the one report showing a negative vantage point of dairy products and dysmenorrhea, I would assert that this simple notion of Calcium 1,000 mg/day starting on day 15 is an important option in trying to reduce the impending menstrual cramps.
Zarei S, Charandabi M, Mirghafourvand M, et al. Effects of calcium-vitamin D and calcium-alone on pain intensity and menstrual blood loss in women with primary dysmenorrhea: a randomized controlled trial. Pain Medicine 2016;0:1-11.