Menstruation can often come with a degree of discomfort as the uterus prepares to shed. For some, the effects can be horrendous.

It's estimated that some 5 to 8 percent of women experience moderate to severe symptoms that have a noticeably negative impact on their lives, mental health, and ability to function normally. These premenstrual disorders, or PMDs, affect millions of women globally, yet we know shockingly little about their long-term consequences.

Now, a new nationwide observational study in Sweden has shown that women with PMDs have an increased risk of suicide. In fact, they're more than twice as likely to die by suicide as women without PMDs. It's a sobering figure, one that strongly suggests more work needs to be done to understand PMDs, and help the people who suffer from them.

"The findings of this matched cohort study suggest that women with PMDs are not at increased risk of early death overall," write a team led by women's mental health epidemiologist Marion Opatowski of the Karolinska Institute in Sweden.

"However, the risk was elevated among young women and for death by suicide. This supports the importance of careful follow-up for young patients and highlights the need to develop suicide prevention strategies for all women with PMDs."

On average, people who menstruate will have around 480 periods in their lifetimes, on a cycle that typically lasts between 23 to 38 days. The premenstrual period goes for approximately one week before menstruation begins, accounting for around a quarter of the entire cycle. That equates to a lot of time experiencing premenstrual symptoms, especially for those with disorders. The most severe of these, premenstrual dysphoric disorder, includes severe depression, anxiety, anger, and mood swings.

Previous studies found that women who suffer from these disorders are at an increased risk of injury due to accident, as well as having an increased presentation of suicidal behaviors. Opatowski and her colleagues sought further understanding by investigating the link between PMDs and mortality by conducting a cohort study.

This is a type of study that follows a specific group of people over a period of time to observe changes in that population. They used multiple Swedish population registers to trace mortality outcomes for 67,748 women diagnosed with PMDs between 1 January 2001 and 31 December 2018, randomly matching each patient to five women who had not been diagnosed with PMDs, for a total of 406,488 women.

Then, they studied the mortality rates for these groups, as well as cause of death. There were 367 deaths observed among women with PMDs, or 8.4 deaths per 10,000 person-years; and 1,958 deaths observed among women without PMDs, or 9.1 deaths per 10,000 person-years.

This means, overall, women with diagnosed PMDs did not have a higher risk of mortality. But there was a higher risk of death due to non-natural causes, such as accidents, but particularly suicide. The incidence of suicide among women with PMDs was 2.3 deaths per 10,000 person-years, compared to 1.06 deaths per 10,000 person-years for women without PMDs.

Earlier research found that PMDs are highly comorbid with psychiatric disorders, which tend to be associated with higher mortality rates. But even after accounting for this, the elevated risk remains.

The study does not go into why the link exists – the main aim was to establish whether there was one to be found for any cause of death.

Interestingly, women with PMDs were found to have a lower risk of death associated with cardiovascular causes. This could be because these women maintain closer contact with their health providers. Or it may have something to do with medication; the selective serotonin reuptake inhibitor antidepressants often prescribed for PMDs can confer protection against some cardiovascular diseases, as can hormone replacement therapy.

It seems clear, now, that a link exists. Further investigation will help establish why – and hopefully figure out some ways to prevent it.

The research has been published in JAMA Network Open.

If this story has raised concerns or you need to talk to someone, please consult this list to find a 24/7 crisis hotline in your country, and reach out for help.