Tiziana Ruggiero (238561) & Francesca Bar (239273)
The intensity of musculoskeletal pain associated with temporomandibular disorders [TMDs] varies systematically across the menstrual cycle.
During the normal menstrual cycle, estrogen levels are at their lowest during menses. Estrogen secretion increases gradually during the early part of the follicular phase and then exponentially in the days before ovulation. Ovulation occurs approximately 10–12 h after the LH peak, around Day 14 in the ‘typical’ menstrual cycle. There is a precipitous drop in estrogen in the days following ovulation and then a gradual increase during the early to mid luteal phase. Estrogen then drops again during the late luteal phase just before menses.
● Women taking OCs have an estrogen drop at the end of the cycle when they cease to take active medication, and have relatively low levels of estrogen at the time of menses. However, they do not have the fluctuation in estrogen associated with ovulation.
● For normally cycling women with TMD, facial pain rose at a time corresponding to the late luteal estrogen drop and peaked during menses when estrogen reaches its lowest level.
● Women with TMD taking OCs display a similar pattern.
● However, only ovulating women show a secondary pain peak during the days around ovulation when estrogen levels are changing exponentially.
Although the evidence is less clear than for migraine, a number of prospective diary studies have found indications that estrogen fluctuations may be associated with non-migraine headaches as well. The incidence of both migraine and non-migrainous headaches is significantly higher during the menstrual period than during the remainder of the cycle
The risk of all headaches is elevated during the first three days of menstruation, although the increase in risk is statistically significant only for migraine without aura.
The hypothesis that has been proposed for menstrual migraine is that migraine onset is triggered by the withdrawal of estrogen. Similar mechanisms associated with the effects of estrogen decrease on pain neurotransmitters may account for the exacerbation of ongoing TMD pain.
The highest pain levels occurred at times of low estrogen (i.e. during the menstrual flow), and at times of rapid estrogen change (late luteal and mid-cycle).
Changes in temporomandibular pain and other symptoms across the menstrual cycle