Estrogens and progesterone are not just sex hormones that influence ovulation and reproduction; they also affect a large number of cognitive and affective functions.
New brain imaging research shows how changes in hormones during the menstrual cycle affect how women feel pleasure and reward. Estrogen and progesterone fluctuations affect the reward response in an area of the brain called the mesencephalon, or midbrain. The reward system is related to addiction and pleasure-seeking, and in an experiment researchers looked at the brain with fMRI during a gambling task. They found that during the pre-ovulation (follicular) phase of the menstrual cycle, emotion-processing areas of the brain were more active, and higher estrogen levels increased dopamine transmission and feelings of pleasure. One theory is that it’s related to reproduction by making sex, and the anticipation of it, more vividly pleasurable prior to ovulation and possible conception.
Women’s health and neuroendocrinology are a complex business, but there are a few studies I wanted to note that are indirectly related.
Mood disorders have long been linked to the menstrual cycle, especially PMS and PMDD (premenstrual dysphoric disorder), but bipolar disorder can be affected also. Menopause is linked to depression in women without prior mood disorders, but one study of bipolar women found that 68% experienced at least one depressive episode during menopause, with an increased frequency compared to prior reproductive phases.
Less established, with conflicting reports over the years, is how the menstrual cycle affects the course of bipolar disorder aside from major reproductive events like childbirth and menopause. Some report a correlation with rapid cycling, while other studies find no connection. But there is good news: seems that bipolar women successfully stabilized on medication also experienced relief from menstrual-related symptoms. A Turkish study concluded, “Within the limitations of the study, the results suggest that ongoing mood-stabilizing treatment may have a prophylactic effect against premenstrual symptom changes in women with treatment-responsive BD.”
Other studies show similar results with lithium and valproate (Depakote/Epival), though valproate has a risk of polycystic ovary syndrome, and a high risk of birth defects, so should be used with caution. Women who experience PMDD may find relief with sertraline (Zoloft), an established first-line treatment, though in bipolar disorders monotherapy with an antidepressant is not recommended because it can trigger mania.
Finally, in what seems to be an isolated, but interesting, case report, a woman with a “30-year history of treatment-resistant menstrually-entrained rapid cycling bipolar II disorder with follicular phase [pre-ovulation] depressive and luteal phase [pre-menstrual] mood elevation symptoms” found dramatic relief using lamotrigine (Lamictal). At the time the article was written she had been free of symptoms for an entire year. It’s not clear how lamotrigine may affect hormones, or interconnected brain mechanisms, but for women who suffer from menstrual mood disorders it might be another option to discuss with a doctor.
Maybe if the appointment was during a follicular phase it would heighten anticipation of a rewarding visit? Then again, ob-gyn and psychiatric appointments really aren’t very pleasurable no matter what the hormone levels. How about some chocolate after the consultation?
Read more: Influence of the Menstrual Cycle on the Female Brain from ScienceDaily, based on the research article Menstrual cycle phase modulates reward-related neural function in women, Dreher et al., Proc. Natl. Acad. Science USA, 10.1073/pnas.0605569104 (subscription req’d)