Women have been menstruating throughout history. So it’s curious the earliest documented record of what we now know to be premenstrual syndrome (PMS) appeared pretty late in the game. In 1931, psychoanalyst Karen Horney described increased tension, irritability, depression and anxiety in the week preceding menstruation in one of her patients.
Now it’s generally accepted up to 80 per cent of women in their reproductive years experience some PMS. The condition includes symptoms such as fatigue, poor coordination, feeling out of control, feeling worthless and guilty, headache, anxiety, tension, aches, irritability, mood swings, weight gain, food cravings, no interest in usual activities, cramps, feeling sad or depressed, breast tenderness, sleep problems, and difficulty concentrating.
Premenstrual syndrome is different to premenstrual dysphoric disorder (PMDD), which is rarer (only three to five per cent of women of reproductive age experience it) and is listed in the diagnostic manual of mental disorders.
People who experience PMDD have severe depression which is often accompanied by suicidal thoughts. Their onset and offset usually coincide with the premenstrual cycle. Unlike PMS, the severely depressed mood of PMDD usually comes on suddenly.
Reproductive hormones – oestrogen, progesterone and testosterone – are also potent brain hormones. They influence the brain chemicals responsible for our thoughts, behaviours and emotions. Their amounts fluctuate throughout the menstrual cycle, so the connection between them and mental health is clear. And we are learning more about why some women may be more affected than others.
Brain chemicals and PMS
There is no single clear theory yet to explain exactly which hormones trigger particular chemicals or why only some women experience PMDD or PMS.
But we know some women are susceptible to mood changes due to small fluctuations in reproductive hormones. In these vulnerable women, small changes in oestrogen and progesterone levels lead to shifts in central brain chemicals (GABA, serotonin and dopamine) that then affects mood and behaviour.
At the same time, many of the physical PMS symptoms such as breast tenderness, bloating, headaches and constipation are a direct effect of reproductive hormones. So both mind and body are affected.
Oestrogen appears to be a “protective” hormone, which can improve psychotic symptoms (such as those common in schizophrenia) as well as depression. Oestrogen directly influences the neurotransmitters serotonin and dopamine to achieve this positive effect.