Sex and the brain
How the menstrual cycle relates to sexual desire
Sexual desire rises during the follicular phase, peaks at ovulation, and declines in the luteal phase. It’s important to note that although sexual desire peaks at ovulation, sexual desire can be present throughout the entire menstrual cycle.1
HSDD is prevalent among women at all reproductive stages, whether in their fertile years or menopausal years. This suggests that reproductive hormones are not the whole underlying story5,6
- In fact, neuroanatomical, neuroendocrine, and neurochemical systems of the CNS all contribute to sexual response, involving interactions between sex steroids and neurotransmitters in the brain7
- Brain pathways for sexual excitation and inhibition have been identified and are being studied. Collectively, the behavioral patterns stimulated by these pathways manifest in sexual desire/inhibited sexual desire8
Sexual function requires the complex interaction of multiple neurotransmitters and hormones, both centrally and peripherally8,9
- Sexual desire depends on the activation of neurochemical systems for sexual excitation by erotic cues8
- The activation and release of dopamine by dopaminergic neurons in the hypothalamus is one of the physiologic mechanisms that affect desire8
- This dopamine release is partially driven by the activation of melanocortin 4 receptors (MC4Rs) by melanocyte-stimulating hormones (MSHs)8
In women with HSDD compared with no HSDD…
PET scans show markedly less blood flow to areas of the brain that are important in sexual response10
The left brain is responsible for normal daily activities, such as work. For a normal sexual response to occur, the left hemisphere needs to be deactivated, as evidenced by the larger areas of red (deactivation) in women with no HSDD vs women with HSDD when shown an erotic video.10,11
The right brain needs to be activated for a normal sexual response. The green (activation) area is larger in women with no HSDD than the area in women with HSDD when shown an erotic video. As the PET scan reveals, there is less blood flow in women with HSDD in these brain areas that are critical for sexual function.10,11
Brain activity and female sexual dysfunction
Jim Pfaus, PhD
Dr. Pfaus is a consultant for AMAG Pharmaceuticals, Inc. and Palatin Technologies, Inc.
HSDD=hypoactive sexual desire disorder.
Imaging studies demonstrate differences in brain structure in women with HSDD and women without HSDD11-13
- Women with HSDD, as compared with controls, had reduced gray matter (GM) volume and increased white matter (WM) volume
- Sexual interest and arousal correlated mostly with GM volume
References: 1. Stuckey BG. Female sexual function and dysfunction in the reproductive years: the influence of endogenous and exogenous sex hormones. J Sex Med. 2008;5(10):2282‐2290. 2. Pfaus JG, Jones SL, Flanagan-Cato LM, Blaustein JD. Female sexual behavior. In: Plant T, Zeleznik A, eds. Knobil and Neill’s Physiology of Reproduction. 4th ed. New York, NY: Elsevier; 2015:2287-2370. 3. Slob AK, Ernste M, van der Werff ten Bosch JJ. Menstrual cycle phase and sexual arousability in women. Arch Sex Behav. 1991;20(6):567-577. 4. Stanislaw H, Rice FJ. Correlation between sexual desire and menstrual cycle characteristics. Arch Sex Behav. 1988;17(6):499-508. 5. Leiblum SR, Koochaki PE, Rodenberg CA, Barton IP, Rosen RC. Hypoactive sexual desire disorder in postmenopausal women: US results from the Women’s International Study of Health and Sexuality (WISHeS). Menopause. 2006;13(1):46-56. 6. Rosen RC, Connor MK, Maserejian NN. The HSDD registry for women: a novel patient registry for women with generalized acquired hypoactive sexual desire disorder. J Sex Med. 2010;7(5):1747-1756. 7. Perelman M. Clinical application of CNS-acting agents in FSD. J Sex Med. 2007;4(4):280-290. 8. Pfaus JG. Pathways of sexual desire. J Sex Med. 2009;6(6):1506-1533. 9. Clayton AH, Hamilton DV. Female sexual dysfunction. Obstet Gynecol Clin North Am. 2009;36(4):861-876. 10. Goldstein I, Kim NN, Clayton AH, et al. Hypoactive sexual desire disorder. International Society for the Study of Women’s Sexual Health (ISSWSH) expert consensus panel review. Mayo Clin Proc. 2017;92(1):114-128. 11. Holstege G. How the emotional motor system controls pelvic organs. J Sex Med. 2016;4(4):303-328. 12. Bloemers J, Scholte SH, van Rooij K, et al. Reduced gray matter volume and increased white matter fractional anisotropy in women with hypoactive sexual desire disorder. J Sex Med. 2014;11(3):753-767. 13. Arnow BA, Millheiser L, Garrett A, et al. Women with hypoactive sexual desire disorder compared to normal females: a functional magnetic resonance imaging study. Neuroscience. 2009;158(2):484-502.