Vitamin D and menstrual cramps

Dysmenorrhea, the medical term for menstrual cramps, is a common problem affecting over 50 percent of menstruating women of all ages.

The term “dysmenorrhea” is derived from Greek, meaning “difficult monthly flow,” thus referring to the pain experienced by women during their monthly cycle. Pain is often experienced just before or during the first two days of the menstrual period and will usually ease as the period continues. The pain can be in the pelvic region, lower back or may even radiate down the thighs. For some women, nausea, vomiting, fatigue, headache, increased urination and diarrhea may accompany the pain. It can be so debilitating for some that they are forced to take time off work or school, disrupting social and family life. It is estimated that 10 percent of women who experience menstrual cramps are rendered incapacitated for one to three days each month.

Menstrual cramps can be classified as primary (physiological problem) or secondary (caused by underlying pelvic abnormality such as uterine fibroids or endometriosis).

Primary dysmenorrhea starts after the release of inflammatory compounds called prostaglandins from the endometrial cells inside the uterus. And therefore target treatment is often focused on the suppression of these prostaglandins. Treatments may include non-steroidal anti-inflammatory drugs (NSAIDS), herbs, nutritional supplements and/or hormonal contraceptives.

Vitamin D has received much attention in the past few years regarding its role in calcium balance, bone health and immune function. Vitamin D can also reduce the expression of the inflammatory compound cyclooxygenase-2 and can therefore regulate prostaglandin production, exerting anti-inflammatory effects in the body and endometrium.

A randomized double-blind placebo-controlled clinical trial was conducted on 60 women with primary dysmenorrhea and vitamin D deficiency. Women had to have at least four recent consecutive menstrual cycles with painful cramps during the previous six months. Women also had to have a serum vitamin D level of <50ng/ml.

Women in the treatment group received 50,000 oral vitamin D once per week for 8 weeks, while 30 women received placebo once a week for 8 weeks.

In the vitamin D treatment group prior to treatment, pain was mild in three (13 percent), moderate in 16 (69.6 percent) and severe in four (17.4 percent) of the women. After treatment (two months), 22 (95.7 percent) had mild pain, one (4.3 percent) had moderate pain and none had severe pain.

Pain intensity significantly decreased in the treatment group after eight weeks of treatment, with a significant difference in pain intensity between the two groups.

Vitamin D may be a useful and inexpensive strategy to reduce primary dysmenorrhea along with lifestyle and dietary recommendations.