Greater prevalence of anaemia and heavy menstrual bleeding reported in women of reproductive age in the United Kingdom compared to Australia.

Heavy periods are a common cause of anaemia in women of reproductive age. We compare the prevalence of anaemia and heavy menstrual bleeding (HMB) among women in the United Kingdom and Australia. Women aged 15-50 years were recruited through screening events conducted in the United Kingdom and Australia from 2016 to 2024. In these cross-sectional studies, self-report questionnaires screened for HMB and finger prick haemoglobin concentration (Hb) identified anaemia (Hb < 120 g/L). Of 1937 women (United Kingdom = 333, Australia = 1604), the mean age was 28.5 ± 9.2 years and 33.7% reported HMB. In the United Kingdom, the mean Hb was 129.2 ± 12.0 g/L and 19.2% were anaemic, of which 59.4% had HMB. In Australia, the mean Hb was higher (134.4 ± 12.2 g/L; p < 0.001), with fewer women being anaemic (9.7%; p < 0.001), and fewer anaemic women had HMB (30.3%; p < 0.001). Logistic regression analysis found that women in the United Kingdom were at a greater risk of being anaemic (AOR: 2.144; 95%CI:1.545, 2.946; p < 0.001). HMB was more common in the United Kingdom (45.9% vs. 31.2%; p < 0.001). In Australia, 24.7% (299/1211) reported receiving intravenous iron; while those with prior intravenous iron treatment were less likely to be anaemic (AOR: 0.616; 95%CI: 0.372, 0.982; p = 0.0496). Women in the United Kingdom are more likely to have anaemia and HMB than women in Australia, with HMB presenting a greater risk for anaemia development in the United Kingdom.