Objective: To evaluate the association between contemporary hormonal contraceptive use and the risk of incident ischaemic stroke and myocardial infarction. Design: Real-world, nationwide, prospective cohort study. Setting: Denmark, by use of national registries. Participants: All women aged 15-49 years residing in Denmark between 1996 and 2021, with no history of arterial or venous thrombosis, antipsychotics use, cancer, thrombophilia, liver disease, kidney disease, polycystic ovary syndrome, endometriosis, infertility treatment, hormone therapy use, oophorectomy, and hysterectomy. Main outcome measures: First time diagnosis of ischaemic stroke or myocardial infarction at discharge. Results: Among 2 025 691 women followed up for 22 209 697 person years, 4730 ischaemic strokes and 2072 myocardial infarctions occurred. Standardised ischaemic stroke rate per 100 000 person years were 18 (95% confidence interval 18 to 19) for no use, 39 (36 to 42) for combined oral contraception, 33 (25 to 44) for progestin-only pills, and 23 (17 to 29) for intrauterine device. Standardised myocardial infarction rate per 100 000 person years were 8 (8 to 9) for no use, 18 (16 to 20) for combined oral contraception, 13 (8 to 19) for progestin-only pills, and 11 (7 to 16) for intrauterine device. Compared with no use, current use of combined oral contraception was associated with an adjusted rate ratio of 2.0 (1.9 to 2.2) for ischaemic stroke and 2.0 (1.7 to 2.2) for myocardial infarction. These corresponded to standardised rate differences of 21 (18 to 24) extra ischaemic strokes and 10 (7 to 12) extra myocardial infarctions per 100 000 person years. Compared with no use, current use of progestin-only pills was associated with an adjusted rate ratio of 1.6 (95% CI 1.3 to 2.0) for ischaemic stroke and 1.5 (1.1 to 2.1) for myocardial infarction, equating to 15 (6 to 24) extra ischaemic strokes and four (−1 to 9) extra myocardial infarctions per 100 000 person years. Increased arterial thrombotic risk was also observed with use of the combined vaginal ring (adjusted incidence rate ratio of 2.4 (1.5 to 3.7) for ischaemic stroke and 3.8 (2.0 to 7.3) for myocardial infarction), patch (3.4 (1.3 to 9.1) and no myocardial infarctions), and progestin-only implant (2.1 (1.2 to 3.8) and ≤3 myocardial infarctions), whereas no increased risk was observed with progestin-only intrauterine device (1.1 (1.0 to 1.3) for ischaemic stroke and 1.1 (0.9 to 1.3) for myocardial infarction). Conclusions: Use of contemporary oestrogen-progestin and progestin-only contraceptives was associated with an increased risk of ischaemic stroke and, in some cases, myocardial infarction except for the levonorgestrel-releasing intrauterine device, which was not associated with either. Although absolute risks were low, clinicians should include the potential risk of arterial thrombosis in their assessment of the benefits and risks when prescribing a hormonal contraceptive method.

Oral tranexamic acid is effective for heavy menstrual bleeding, but the thrombosis risk with this treatment is largely not studied. Using nationwide registries, we assessed associations between use of oral tranexamic acid and risk of deep-vein thrombosis or pulmonary embolism and arterial thrombosis in heart or brain in a nationwide historical prospective cohort of Danish women aged 15 to 49 years in the period 1996–2017. Exclusion criteria included potential confounding factors such as history of thromboembolism, anticoagulation therapy, thrombophilia, and cancer. Among 2·0 million women followed for 13·8 million person-years, 3,392 venous thromboembolisms and 4,198 arterial thromboses occurred. A total of 63,896 women (3·2%) filled 146,729 prescriptions of oral tranexamic acid during follow-up with median filled prescription per user being one of 15 g. The age-standardised incidence rate of venous thromboembolism was 11·8 (95% CI 4·6 to 30·2) per 10,000 person-years in oral tranexamic acid use compared to 2·5 (2·4 to 2·6) per 10,000 person-years in non-use. For arterial thrombosis, the age-standardised incidence rate per 10,000 person-years was 3·4 (1·1 to 10·7) among exposed compared to 3·0 (2·9 to 3·1) in non-exposed. Comparing oral tranexamic acid use with non-use, the adjusted incidence rate ratio was 4·0 (1·8 to 8·8) for venous thromboembolism and 1·3 (0·4 to 4·2) for arterial thrombosis. Number needed to harm per five days of treatment was 78,549 women for venous thromboembolism. We found use of oral tranexamic acid to be positively associated with venous thromboembolism. However, number needed to harm per five days of treatment was high.

Background: Colorectal cancer screening program using a fecal immunochemical test aims to reduce morbidity and mortality through early detection. Although screening participation is free-of-charge, almost 40% of the invited individuals choose not to participate. To bring new insight into how non-participation can be identified and targeted, we examined the association between marital status and screening participation; with a focus on partner concordance in participation and sex differences. Methods: This nationwide cross-sectional study included all Danish citizens aged 50–74 years, who were invited to colorectal cancer screening between 2014 and 2017. Logistic regression analysis was used to estimate odds ratio (OR) of participation while adjusting for sociodemographic variables. Results: A total of 1 909 662 individuals were included in the analysis of which 62.7% participated in the screening program. Participation was highest among women. Stratified by marital status, screening participation was markedly lower in widowed (61.5%), divorced (54.8%) and single (47.3%), while participation reached 68.4% in married individuals. This corresponded to ORs of 0.59 (95% CI 0.58–0.59) for widowed, 0.56 (95% CI 0.55–0.56) for divorced and 0.47 (95% CI 0.47–0.48) for single, compared to married individuals. Individuals married to a participating partner were five times more likely to participate than married individuals with a non-participating partner, regardless of gender. Conclusions: Marital status was strongly associated with participation in colorectal cancer screening, and participation was even higher in married individuals with a participating partner. Future efforts to increase participation in colorectal cancer screening could potentially benefit from considering the role of partner concordance.