Vitamin D Fights Menstrual Cramps

Menstrual cramps eased with vitamin d

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Do you constantly battle severe cramps? A new study says that a surge of the “sunshine vitamin” may be able to help.

A single high dose of vitamin D can ease severe menstrual cramps, reports one small Italian study. However, the large dose used in the study is higher than the recommended amount for people, say experts.

"Ask your doctor about severe menstrual pain treatment."

Researchers at the University of Messina in Italy studied 40 women with severe menstrual cramps, known as dysmenorrhea. They wanted to examine vitamin D’s effect on menstrual cramps because of vitamin D’s impact on immune cells and the uterus, and also because it blocks the synthesis of prostaglandin, which reduces pain.

The women, ranging from 18 to 40 years of age, all had at least four consecutive painful menstrual periods during a six-month period and serum levels of 25-hydroxyvitamin-D below 45 ng/mL.

The women were divided into two groups: half of the women were given an oral dose of 300,000-IU of vitamin D five days before their next expected menstrual period, and the other half took a placebo.

Dysmenorrhea affects about half of all women who menstruate and is the leading cause of work and school absenteeism among women in their teens and 20s, according to the National Institutes of Health.

The researchers had the women report their level of pain on a 10-point visual analog scale for four cycles before beginning treatment and two cycles while receiving treatment.

At the end of treatment, 15 of the women who took vitamin D reported pain scores that were two points lower than their baseline average over the four-month non-treatment phase, reports lead study investigator Dr. Antonio Lasco of the University of Messina and colleagues in the study. And all of the women in the vitamin D group reported some improvement in pain.

Most patients in the placebo group had no change in pain, though 4 women reported a one-point decrease in pain, say the researchers.

The women in the vitamin D group also did not report needing to use nonsteroidal anti-inflammatory drugs (NSAIDs) to ease pain during treatment.

NSAIDs are the standard form of treatment for dysmenorrhea.

However, eight women taking placebo took the painkiller at least once.

In a commentary that accompanied the study, two researchers warned that the dose of vitamin D used in the study was higher than the “tolerable upper limit” established by the U.S. Institute of Medicine, which is 240,000-IU over two months, or 4,000-IU a day.

The two researchers, Dr. Elizabeth R. Bertone-Johnson of the University of Massachusetts in Amherst and Dr. JoAnn E. Manson of Brigham and Women’s Hospital in Boston, say that more trials – with a larger number of participants and that stretch over a longer period of time – are needed. Further studies can also examine how long vitamin D treatment lasts and how often doses should be given, they say.

Bertone-Johnson and Manson note say that dysmenorrhea is caused by an excessive production of prostaglandins in the uterus. The condition can also be a side effect of a number of conditions, including endometriosis, uterine fibroids, adenomyosis, pelvic inflammatory disease, and cervical stenosis, according to the Mayo Clinic.

This observational study was published in the Archives of Internal Medicine.

Reviewed by: 
Review Date: 
February 29, 2012
Last Updated:
March 3, 2012