MAGDALENE.BY LATERAL THINKERS

03 / The Facts

The research behind every claim.

53 source entries and 120 evidence points, compiled 19 October 2026. This is an index of sources, not a new systematic review, and a listing is not an endorsement.

Key statistics, in exact wording

44%

Of UK girls aged 12–18 who had started periods, 44% in the Wellbeing of Women December 2023 survey reported being unable to participate in sport/physical activity due to period symptoms. Surveyed: 3,001 girls; 2,620 had started periods. Does not mean 44% of all adult women miss sport or permanently quit.

83%

In a UK August 2023 survey of 3,002 women and girls aged 16–40, 83% agreed that better period education is needed in school, college and university. A separate 83% response concerned accessible information about gynaecological conditions.

82%

Same August 2023 survey: 82% agreed that more accurate, accessible information on periods is needed.

51%

In a separate February 2025 UK consumer survey, 51% of surveyed women said they avoid exercise while on their period. Do not merge with 2023 girls survey.

36%, 20%, 11%

In the 2023 girls survey, 36% missed school/education, 20% said bedbound, 11% said symptoms made life feel not worth living. The last is a self-report, not a suicide count.

18.7% / 40.0%

Palmer et al., England cross-sectional online sample: severe period pain 18.7%; heavy bleeding 40.0% in past year. Ages 16-55; n=59,332 total, outcomes vary by response.

9 years 4 months

Endometriosis UK March 2026 charity-survey average reported time to diagnosis; not an NHS administrative national average.

69%

CIPD 2023 UK workplace survey: 69% of symptomatic respondents said menstrual symptoms negatively affected work; not annual absence rate.

Menstrual Health Research Review

Pages from the review. Tap a page to open it full size.

Research review page 1Research review page 2Research review page 3Research review page 4Research review page 5Research review page 6Research review page 7

All sources

Clinical / professional guidance

  1. [01]NHS. Water, drinks and hydration. Practical fluid guidance.Open source
  2. [07]Drinking Water Inspectorate. Chlorine; domestic water filters and softeners. Disinfection and maintenance guidance.Open source
  3. [10]NHS. Antacids. Ingredients, cautions and interactions.Open source
  4. [12]World Cancer Research Fund. Wholegrains, vegetables, fruit and beans; evidence supporting cancer-prevention recommendations.Open source
  5. [18]NHS. Periods and fertility in the menstrual cycle.Open source
  6. [19]NHS. Period problems: care and treatment options.Open source
  7. [24]NHS. Periods. Typical timing and duration.Open source
  8. [25]NHS. Period pain. Self-care, causes, treatment and urgent advice.Open source
  9. [26]NHS. Heavy periods. Symptoms, investigation and treatments.Open source
  10. [27]NHS. Iron deficiency anaemia. Symptoms, causes and treatment.Open source
  11. [28]NHS. Endometriosis. Symptoms and care options.Open source
  12. [29]NHS. PMS and PMDD. Symptoms and treatment.Open source
  13. [30]NHS. Postmenopausal bleeding. Assessment even after a single episode.Open source
  14. [31]NHS. Pelvic pain. Urgent and emergency advice.Open source
  15. [35]NHS. PMDD: symptoms, timing and treatment.Open source
  16. [36]NHS. PMS: symptoms, treatment and evidence limits.Open source
  17. [43]NHS. Diabetic ketoacidosis.Open source
  18. [44]RCOG. Managing PMS: timing and care.Open source
  19. [45]NHS Scotland / SIGN. Menstrual migraine: timing and treatment.Open source
  20. [50]NHS. Adult physical activity guidelines.Open source
  21. [51]NHS. Mindfulness.Open source
  22. [52]NHS. Salt in your diet.Open source
  23. [53]NHS. Breathing exercises for stress.Open source

Peer-reviewed study / review

  1. [02]Wittbrodt MT, Millard-Stafford M (2018). Dehydration Impairs Cognitive Performance: A Meta-analysis. Med Sci Sports Exerc 50:2360-2368. DOI: 10.1249/MSS.0000000000001682.Open source
  2. [03]Windham GC et al. (2003). Chlorination by-products in drinking water and menstrual cycle function. Environ Health Perspect 111:935-941. DOI: 10.1289/ehp.5922.Open source
  3. [04]Exogenous and Endogenous Determinants of Blood Trihalomethane Levels after Showering (2008). Controlled exposure study.Open source
  4. [05]The influence of physicochemical properties on the internal dose of trihalomethanes in humans following a controlled showering exposure (2012).Open source
  5. [06]The role of water intake in the severity of pain and menstrual distress among females suffering from primary dysmenorrhea: a semi-experimental study (2021). Preliminary intervention evidence.Open source
  6. [08]Fenton TR, Huang T (2016). Systematic review of the association between dietary acid load, alkaline water and cancer. BMJ Open 6:e010438. DOI: 10.1136/bmjopen-2015-010438.Open source
  7. [09]International Society of Sports Nutrition position stand: sodium bicarbonate and exercise performance (2021). DOI: 10.1186/s12970-021-00458-w.Open source
  8. [11]Estruch R et al. (2018). Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. Revised PREDIMED report. NEJM 378:e34. DOI: 10.1056/NEJMoa1800389.Open source
  9. [13]Exposure to Drinking Water Trihalomethanes and Risk of Cancer: A Systematic Review of the Epidemiologic Evidence and Dose-Response Meta-Analysis (2025). DOI: 10.1289/EHP14505. Observational exposure evidence.Open source
  10. [16]Palmer MJ et al. (2025). The Burden of Poor Reproductive Health in England. BJOG. DOI: 10.1111/1471-0528.18133. Age-weighted online convenience survey; not a UK age-12+ census.Open source
  11. [22]Liu XY et al. (2024; online 2023). Urinary biomarkers of drinking-water disinfection byproducts in relation to diminished ovarian reserve risk. DOI: 10.1016/j.scitotenv.2023.168729.Open source
  12. [23]Exposure to disinfection by-products and risk of diminished ovarian reserve: Case-control evidence and cellular metabolomic insights (2025). DOI: 10.1016/j.reprotox.2025.108901. Bibliographic/abstract verification; full text not obtained.Open source
  13. [37]Jang D et al. (2025). Menstrual cycle effects on cognitive performance: a meta-analysis. DOI 10.1371/journal.pone.0318576.Open source
  14. [38]Prasad D et al. (2021). Suicidal risk in PMS/PMDD: systematic review and meta-analysis. DOI 10.1089/jwh.2021.0185.Open source
  15. [39]Suicidality in patients with PMDD: systematic review and meta-analysis (2021). Different estimates.Open source
  16. [40]Dos’Santos T et al. (2023). Menstrual phase and ACL injury-risk surrogates: systematic review. DOI 10.1371/journal.pone.0280800.Open source
  17. [42]Schoep ME et al. (2019). Productivity loss: Dutch survey of 32,748 women. DOI 10.1136/bmjopen-2018-026186.Open source
  18. [46]Reilly et al. (2024). PMDD prevalence review. DOI 10.1016/j.jad.2024.01.066. Confirmed community estimate 1.6%.Open source
  19. [47]Dietary acid load in health and disease (2024). DOI 10.1007/s00424-024-02910-7.Open source
  20. [48]EPIC-Norfolk: urine pH as an indicator of dietary acid-base load (2008).Open source

Survey / policy / public research reporting

  1. [17]LSHTM (2025). Population application of the reproductive-health survey: more than 10 million in England, encompassing multiple reproductive outcomes.Open source
  2. [20]House of Commons Women and Equalities Committee (2026). Menstrual health of girls and young women.Open source
  3. [21]Wellbeing of Women. December 2023 girls survey executive summary. UK ages 12-18; self-reported impacts.Open source
  4. [32]CIPD (2023). Menstruation and support at work. UK survey.Open source
  5. [33]Endometriosis UK (2 March 2026). Diagnosis report findings: 9 years 4 months.Open source
  6. [34]Wellbeing of Women. Just a Period: surveys from August/December 2023 and February 2025. Do not merge populations.Open source
  7. [41]ActionAid UK (2026). Poll: 11% struggled to afford period products.Open source

Advertising / data protection / other

  1. [14]ASA/CAP. Weight control: Testimonials; Food and Food Supplements. Advertising rules differ by product category.Open source
  2. [15]Information Commissioner's Office. Special category data and valid consent. Article 6 and Article 9 requirements.Open source
  3. [49]Primary Christian texts: Luke 8:1-3 and John 20:11-18, USCCB. The spiritual framing is contemporary inspiration.Open source
Evidence explained →Sport & Community →