Introduction to PMS
Premenstrual syndrome (PMS) was first described by Frank and Horney in 1931. It is a common cause of physical, behavioural and social dysfunction in women of reproductive age that occurs cyclically and recurrently, starting 1-2 weeks before the menstrual period (the luteal phase of the cycle). Often the symptoms of PMS manifest themselves as irritability, hence why the condition used to be called premenstrual tension (PMT). A characteristic of the syndrome is that all symptoms are relieved by the onset of, or during menstruation.
The precise cause of PMS is still unknown, and relatively little research has been conducted on this condition. Most women experience mild emotional or physical premenstrual symptoms, but for some 8-20% it can severely disrupt their lives to the extent that they seek medical treatment . The most severe form of the syndrome affects between 3% to 5% of women of reproductive age and under the Diagnostics and Statistical Manual of Mental Disorders is known as premenstrual dysphoric disorder (PMDD)
It is thought that PMS may be caused by an increased sensitivity to circulating progesterone and its metabolites rather than abnormal concentrations of hormones . Sex steroids produced by the corpus luteum of the ovary are thought to be symptom provoking, as the cyclicity disappears in anovulatory cycles when a corpus luteum is not formed. The response systems within the brain known to be involved in PMS symptoms are the serotonin and gamma-amino butyric acid (GABA) systems. Progesterone metabolites, especially allopregnanolone, are neuroactive, acting via the GABA system in the brain. Drugs such as SSRIs and substances inhibiting ovulation, such as gonadotrophin-releasing hormone (GnRH) agonists, have proven to be effective treatments. Differences in leptin levels between PMS subjects and controls have also been observed which could point to a role of leptin in the pathophysiology of the disease .
An older theory, but one which still re-emerges, is that PMS can be caused by a lack of production of prostaglandin E1 (PGE1) which is derived from omega 6 fatty acids. It is believed that in PMS there is insufficient delta 6 desaturase enzyme around to convert the Linoleic acid to Gamma linolenic acid and therefore insufficient PGE1 is formed. Insufficient PGE1 is believed to cause undue sensitivity to the luteal phase rise in ovarian hormones.
Various vitamins and minerals and fatty acids, including B Vitamins and Magnesium are involved as co-enzymes in the production of these neurotransmitters and hence why some believe supplementing the diet with them helps to reduce PMS symptoms although, except for magnesium, a true deficiency in any particular nutrient has been hard to show.
Symptoms of PMS vary from woman to woman and each month women can individually experience different symptoms. These include mood swings, irritability, increased appetite, carbohydrate and alcohol cravings, breast tenderness, headaches and bloating.
It is believed that having other underlying chronic diseases such as diabetes, IBS, allergies etc can also lower the threshold for developing PMS. This also ties in with the finding that women with higher levels of C reactive protein (CRP) have more severe premenstrual symptomsal. Making sure that any other chronic medical condition is controlled as best as possible can help reduce the chance of more severe PMS symptoms emerging .
PMS can be hard to diagnose, as many conditions can worsen during the premenstrual phase, such as allergies and even conditions such as migraine and asthma, but this in itself is not an indication that PMS is present. The only real way of identifying PMS is to keep a symptom diary. Symptoms of PMS will appear in the luteal phase (up to two weeks before the period start) and disappear as soon as a period is fully underway .
There is no single treatment universally recognised for PMS and so women often turn to diet, supplements and alternative approaches to relieve their symptoms. For women with mild to moderate symptoms, lifestyle changes and eating a healthy diet can substantially reduce if not alleviate the symptoms. For those who need to go on to receive further treatment such as drugs, having a baseline healthy diet and keeping physically active can mean the treatment is more successful .