Hormones, energy balance and brain chemistry all play a role in cycle regularity and mood. Discover what distinguishes these disorders, clear up common myths and explore lifestyle, medical and mental-health options that can help restore balance.

References & additional material

NHS website for PCOS overview and symptoms
- [https://www.nhs.uk/conditions/polycystic-ovary-syndrome-pcos/]
PCOS prevalence 6-10% depending on diagnostic criteria
- Bozdag, G., Mumusoglu, S., Zengin, D., Karabulut, E. & Yildiz, B. O. The prevalence and phenotypic features of polycystic ovary syndrome: a systematic review and meta-analysis. Hum. Reprod. 31, 2841–2855 (2016).
Hypothalamic amenorrhea symptoms
- [https://www.noperiodnowwhat.com/post/diagnosing-hypothalamic-amenorrhea]
- [https://cks.nice.org.uk/topics/amenorrhoea/]
NHS website for PMS and PMDD
- [https://www.nhs.uk/conditions/pre-menstrual-syndrome/]
PMDD estimated to affect 1.6% of women and girls globally
- Hantsoo, L. & Epperson, C. N. Premenstrual dysphoric disorder: Epidemiology and treatment. Curr. Psychiatry Rep. 17, 87 (2015).
Progesterone metabolites’ effect on GABA receptors
- Del Río, J. P. et al. Steroid hormones and their action in women’s brains: The importance of hormonal balance. Front. Public Health 6, 141 (2018).
DSM5 PMDD diagnostic criteria
- [https://www.ncbi.nlm.nih.gov/books/NBK279045/table/premenstrual-syndrom.table1diag/]

Additional resources

No period, now what? By Nicola Rinaldi
Period power by Maisie Hill – understanding different parts of your cycle and lifestyle modifications that may help