Does PMS cause mood swings?

Question

The Huffington Post writes in Mood Swings From Menstruation May Not Exist, Study Finds:

Premenstrual syndrome, or PMS, may be an utter myth, according to new research from the University of Toronto. The study found that there was no obvious link between women's negative mood swings and the premenstrual phase of their cycles, according to a press release.

Does that finding reflect the scientific consensus around Premenstrual syndrome (PMS)?

Answer 1

Evidence:

1. PMS disorder is a mixture of physical and psychological symptoms associated with mood and hormonal fluctuations before menstruation.

Premenstrual syndrome is defined as recurrent moderate psychological and physical symptoms that occur during the luteal phase of menses and resolve with menstruation. It affects 20 to 32 percent of premenopausal women. Women with premenstrual dysphoric disorder experience affective or somatic symptoms that cause severe dysfunction in social or occupational realms. The disorder affects 3 to 8 percent of premenopausal women. Source: American Family Physician.

2. There is some difference in certain women developing PMS or PMDD since those who develop PMDD are noted to be highly sensitive to hormone level changes.

However, it is not clear why some women develop premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD) and others do not. Levels of estrogen and progesterone are similar in women with and without these conditions. The most likely explanation, based upon several studies, is that women who develop PMDD are highly sensitive to changes in hormone levels. Source: Uptodate

3. Research shows that women in some countries do not report negative mood disorders before menstruation in the same levels as other countries. However, they seem to report the same physical changes.

Researchers have found that women in India, China or Hong Kong report physical changes over the menstrual cycle, but don’t report negative mood premenstrually, or attribute negative mood to PMS. Equally, the longer Asian or Latina women migrants live in the United States, the more likely they are to report PMS. This has led to PMS and PMDD being described as cultural-bound syndromes, challenging the legitimacy of the widespread psychiatric diagnosis of premenstrual mood change. Source: The Conversation

4. Media has a strong bias in reporting negative menstrual cycle changes.

Seventy-eight articles were identified and evaluated for their discussion of symptoms and treatments, the language and terms used in the articles and their titles, and the types of issues covered by different kinds of magazines. The results indicate a strong bias in favor of reporting negative menstrual cycle changes. Articles are generally negative in tone and present a confusing array of symptoms and contradictory treatment recommendations. Source: Women & Health.

Meaning:

1. There are differences between women's experiences of the hormone fluctuations and negative mood experienced before menstruation and there is no confirmation of corelation existing between mood and menstrual cycle.

Romans and her colleagues do not deny the existence of menstrual pain, or even the existence of PMS. What their study shows is that very few women experience cyclic negative mood changes associated with the premenstrual phase of their ovulatory cycle. PMS is not widespread, and the authors are careful to distinguish it from premenstrual dysphoric disorder (PMDD), which is rarer still. As Gillian Einstein, one of the researchers, told the Toronto Star, “We have a menstrual cycle and we have moods, but they don’t necessarily correlate.” Source: MS Magazine.

2. The study mentioned by the OP does not deny the existence of premenstrual dysphoric disorder experienced later in the mensruation or the physical symptoms experienced before menstruation by certain women.

The review did not address the existence of premenstrual dysphoric disorder (PMDD), a clinical mood disorder linked with the menstrual cycle that is characterized by severe physical and behavioural symptoms in the latter half of the menstrual cycle. It also did not discount the existence of physical symptoms such as bloating and cramping related to the pre-menstrual phase. Source: University of Toronto

3. Current research is challenging assumptions about links between premenstrual phase and mood swings.

Culturally held beliefs about PMS seem to have influenced both women's and researchers' expectations of the premenstrual phase, but new research is debunking the existence of negative mood caused by PMS in the general female population. The evidence that we do have for PMS is limited, and psychosocial factors—such as physical health and social support—appear to be more strongly related to mood than any menstrual cycle phase. Research that challenges assumptions about biological links between the premenstrual phase and moodiness may eventually change how society views women's moods and menstruation. Source: Canadian Institutes of Health Research

4. There is no predictable pattern in detecting mood swings in women based on the hormone levels since varying levels might have different mood effects in different women. Men also tend to experience fluctuations in hormones and mood swings but there is no exact mechanism like a menstrual period to track it.

And as for the tradition of portraying women as victims of their changing hormones, it’s possible that men experience the same fluctuations in testosterone, with similar ups and downs in mood and emotional stability. It’s just that it may be easier to attribute the mood swings in women to reproductive hormones because tracking the menstrual cycle provides a noninvasive window into their fluctuations. So while the new review suggests that most women don’t have a predictable pattern of low moods preceding their periods, it doesn’t exonerate reproductive hormones from having any role in how people feel. Source: Time

TL;DR: All women do not experience the same pattern of premenstrual syndrome symptoms and there is no proof of existence of a negative premenstrual mood.

The authors say that, taken together, these studies fail to provide clear evidence in support of the existence of a specific premenstrual negative mood syndrome in the general female population. They say: “This puzzlingly widespread belief needs challenging, as it perpetuates negative concepts linking female reproduction with negative emotionality”. Source: NHS