<p>Extracted data from all included studies.</p>

Quantitative, qualitative, and mixed-methods studies were eligible. Given the heterogeneity in exposures, outcomes, and designs, findings were synthesised narratively. From 3,890 records, 25 studies met inclusion criteria, covering floods (n = 7), air pollution (n = 6), cyclones (n = 3), droughts (n = 3), saltwater intrusion (n = 3), and multiple hazards (n = 4).

Flood- and cyclone-related studies reported disrupted access to menstrual materials, damaged water and sanitation infrastructure, reduced privacy and safety, limited access to care for menstrual disorders, and unsupportive social environments characterised by stigma and restricted mobility. Drought and salinity intrusion constrained hygiene practices through reduced water availability and quality, affecting comfort, dignity, and infection risk.

Across hazards, studies documented adverse physical outcomes, including dermatological irritation and reproductive or urinary tract infections, alongside psychosocial consequences such as shame, anxiety, and harassment. Air pollution studies linked exposures with earlier menarche and menstrual cycle irregularities. Evidence on extreme heat and several MHH domains, including access to information, was limited.

Climate-related hazards undermine multiple, interconnected domains of MHH. The evidence base remains fragmented across hazards, geographies, methods, underscoring the need to integrate MHH into climate adaptation, disaster preparedness, and humanitarian response frameworks and to address critical research gaps related to extreme heat, slow-onset hazards, and equity.</p></div>