What Causes PMDD

As with PMS, the exact cause of PMDD is not known. Most researchers, however, believe PMDD is brought about by the hormonal changes related to the menstrual cycle. The following are some the major theories that may explain PMDD.

1.       The ovarian hormone theory says that PMDD is caused by an imbalance in the ratio of estrogen to progesterone, with a relative deficiency in progesterone. However, recent studies of the level of estrogen and progesterone among women with PMS were inconclusive because of methodological difficulties. The current consensus seems to be that the normal fluctuations in gonadal hormones trigger central biochemical events related to PMDD symptoms.

2.       The serotonin theory says that normal ovarian hormone function (rather than hormone imbalance) is the recurring trigger for PMDD-related biochemical events within the central nervous system and other target tissues. PMDD shares many of the symptoms of depression and anxiety that have been linked to serotonergic dysregulation.  Decreased serotonergic activity in women with PMDD has also been implied by the observation of reduced platelet uptake of serotonin and serotonin levels in peripheral blood. The sensitivity to perturbations of the central serotonin system in women with PMDD is altered premenstrually.

3.       The psychosocial theory says that PMDD or PMS is a conscious expression of a woman's unconscious conflict about femininity and motherhood. Psychoanalysts say that premenstrual physical changes reminded the woman that she was not pregnant and, therefore, was not fulfilling her traditional feminine role. Obviously, proving this theory through scientific evidence is quite difficult.

4.       The cognitive and social learning theory says that the onset of menses is an aversive psychological event for women susceptible to PMDD. Moreover, these women might have had negative and extreme thoughts that further reinforce the aversiveness of premenstrual symptoms. They then develop maladaptive coping strategies, such as moodswings, absence from school or work, and overeating in an attempt to reduce the immediate stress.

5.       The socio-cultural theory says that PMDD is a manifestation of the conflict between the public expectation of the dual role of women as both productive workers and child-rearing mothers. PMDD is assumed to be a cultural expression of women's discontent with the traditional role of women in the society.

Among the theories described above, the serotonin theory is increasingly popular. Although genetic predisposition and public expectations may play a role, the strongest scientific data implicate serotonin as the primary neurotransmitter whose levels are affected by ovarian steroid levels.